CSS - Boxes Sitting Differently On Diff Monitors?

body {
code here;
}

#leftcolumn {
code here;
}

.someelement {
code here;
}

<p id="FillText">Click on an item under <strong>'Latest News'</strong> to read more about it here and get links to the full story...</p>

#FillText {
font-size: 16px;
color: #ffffff;	
height: 280px;
padding-top: 20px;
padding-left: 90px;
padding-right: 15px;
/*padding: 30px 34px 20px 96px;  */
text-indent: 20px;
}

/**
 * @file
 * @project 675
 * @package sftheme
 * @site app1
 */


/** 
 * ------------------------------------------------------------------
 * @section RESETS
 * ------------------------------------------------------------------
 */

body {
    width: 100%;
    height: 100%;
    margin: 0;
    padding: 0;
    border: 0;
	font-family: Verdana, Geneva, Kalimati, sans-serif;
    font-size: 11px;
	color: #ffffff;     
	background-color: #051417;
	
	background-image: url(images/675_background.jpg);
	background-position: center top;
    background-repeat: no-repeat;
	

}

   a:link{color: #ffffff;}
   a:visited{color: #ffffff;}
   a:hover {color: #ffffff;}
   
   .sf_navigation ul li a {color: #ffffff;}
 
   .sf_navigation ul li a:visited {color: #ffffff;}
  
   .sf_navigation ul li a:hover {color: #ffffff;}

   .sf_navigation .subnav li a {color: #ffffff;}
   
   .sf_navigation .subnav li a:visited {color: #ffffff;}

   .sf_navigation .subnav li a:hover {color: #ffffff;}
 
   .sf_footer {color: #ffffff;}

   .sf_pagetitle {color: #ffffff;} /*(WST Only)*/
  

.sf_outer_wrapper {

}

.sf_main_header {
   color: #ffffff;
   font-size: 32px;
   font-family: Verdana, Geneva, Kalimati, sans-serif;
   padding-left: 29px;
}

.sf_pagetitle {
  font-family: Verdana, Geneva, Kalimati, sans-serif;
    font-size: 24px;
    font-weight: normal;
    margin: 0;
    padding-top: 0px;
}

.sf_pagetitle h1{
  font-family: Verdana, Geneva, Kalimati, sans-serif;
    font-size: 24px;
    font-weight: normal;
    margin: 0;
    padding-top: 0px;
}

/** 
 * ------------------------------------------------------------------
 * @section HEADER
 * ------------------------------------------------------------------
 */

.sf_outer_wrapper {
    border-left:1px solid #2D4461;
    border-right:1px solid #2D4461;    
}
* html .sf_outer_wrapper {
    width: 1200px;
}

.sf_main_wrapper{
    width: 600px;
	float: left;
	margin-left: 67px;

}
* html .sf_main_wrapper{
	margin-left: 0px;

}
.sf_wrapper {
    margin:0 0;
    padding:0px 10px;  
	width: 1000px;  
}

* html .sf_wrapper {
	width: 1200px; 
}

.sf_wrapper:after {
	clear:both;
	content:".";
	display:block;
	font-size:1px;
	height:0pt;
	visibility:hidden;
}
.sf_region3 {
    height: 150px;
}

.sf_main_header {
    padding-top: 33px;
    margin: 0px 33px;
    color: #FFFFFF;    
}

/** 
 * ------------------------------------------------------------------
 * @section NAVIGATION
 * ------------------------------------------------------------------
 */

.sf_region4 {
	float: left;
	font-size: 14px;
    width: 200px;
    overflow: visible;
    float: left;
    padding-bottom: 50px;
	padding-right: 50px;
    text-decoration: none;
	margin-top: 53px;
    margin-left: -24px;
    .margin-left:-14px;
}

.sf_navigation .nav a {
	width: 139px;
	padding: 10px;
	font-size: 18px;
}

.sf_navigation .sf_first_nav_item  {
	background-repeat: no-repeat;
	background-position: 0px 0;
	padding-top: 12px;
	border: 0;
}

.sf_navigation {
	 float: left;
    padding-bottom: 50px;
	padding-right: 50px;
    text-decoration: none;
	margin-top: 0px;
    width: 159px;
	margin-left: 77px;
	z-index: 1000;
	position: relative;
}
* html .sf_navigation {
	margin-left: 33px;
}

.sf_navigation .nav .subnav a {
    background-image: none;
	font-size: 12px;
	padding-bottom: 12px;
	padding-top: 12px;
	background-color: #051417;
	background-repeat: no-repeat;
	background-position: top right;
	border: none;
	z-index: 1000;
}
.sf_navigation .nav .subnav a{
    background-color: #051417;
	color: #ffffff;
}
.sf_navigation .nav .subnav a:link{
    background-color: #051417;
	color: #ffffff;
}

.sf_navigation .nav .subnav a:visited{
    background-color: #051417;
	color: #ffffff;
}
.sf_navigation .nav .subnav a:hover {
    background-color: #051417;
	color: #ffffff;
}

.sf_navigation ul {
	padding: 0 0 12px 0;
	margin: 0;
	list-style: none;
	float: left;	
	background-position:0 bottom;
	background-repeat:no-repeat;
}

.sf_navigation:after {
    content: ".";
    display: block;
    visibility: hidden;
    height: 0;
    font-size: 1px;
    clear: both;
}

.widget {
    margin-left: 24px;
}
* html .widget {
    margin-left: 24px;
}

.sf_region4 .sf_navigation .nav a:hover {
    text-decoration: none;
}

.sf_navigation ul li {
	float: left;	
}

.sf_navigation ul li a {
	width: 214px;
	display: block;
	text-decoration: none;
	padding: 0;
    padding-bottom: 12px;
	width: 200px
}

.sf_navigation li ul.subnav {
	padding: 0;
	margin: 0;
	list-style: none;
	float: left;
	width: 160px;
	position: absolute;
	left: -999em;
	margin-left: 158px;
	margin-top: -43px;
	z-index: 1000;
    padding:5px 5px 0;
	background-image: none !important;
	background-color:#051417;
}

.sf_navigation .subnav li {
	float: left;
	margin-bottom: -1px;
	width: 176px;
}

.sf_navigation .subnav li a {
	width: 11em;
	display: block;
	color: #000000;
	text-decoration: none;
	padding: 0;
    margin-bottom: 0px;
}

.sf_navigation .subnav li a:visited {
	color: #000000;
}

.sf_navigation .subnav li a:hover {
	color: #000000;
    text-decoration: none;
}

#Nav1 li:hover, 
#Nav1 li.hover {  
    position: relative;  
}
/* lists nested under hovered list items */
#Nav1 li:hover ul, 
#Nav1 li.sfhover ul { 
	left: auto;
}

#Nav1 iframe{
	position: absolute;
	left: 0;
	top: 0;
	z-index: 0;
    display: none;
}

* html #Nav1 iframe {
    display: inline;
	filter: progid:DXImageTransform.Microsoft.Alpha(style=0,opacity=0);
}

.sf_navigation .widget_header{
    display: none;
}

.sf_navigation ul.subnav a {
    color: #FFFFFF;
}

.sf_navigation ul.subnav a:hover {
    color: #a4bedf;
}

.sf_navigation ul.subnav a:visited {
    color: #FFFFFF;
}

/** 
 * ------------------------------------------------------------------
 * @section MAINCONTENT
 * ------------------------------------------------------------------
 */

.sf_pagetitle {
	margin-left: 316px;
	width: 600px;
	margin-bottom: 20px;
	padding-bottom: 10px;

}

* html .sf_pagetitle {
    margin-left: 5px;
}


.sf_pagetitle h1 {
    padding-right: 22px;
}

.sf_main_wrapper {
    margin-top:-25px;
    padding-bottom: 50px;
}

.sf_content {
    padding-left:27px;
    padding-top:21px;
	float: left;
	width: 600px;
}

* html .sf_content {
	padding-left:0px;
    width: 700px;
}


/** 
 * ------------------------------------------------------------------
 * @section FOOTER
 * ------------------------------------------------------------------
 */

.sf_footer{
    width: 425px;
    margin: 0px auto;
    padding-top: 60px;
    padding-bottom: 20px;
}

a:hover {
   text-decoration: none;
} 
* html a {position:realtive}

<style>
.class1 {float:left;width:100px;background:first_tab.jpg }
.class2 {float:left;width:100px;background:tab.jpg }
.class3 {float:left;width:100px;background:last_tab.jpg }
</style>

<div class="clearfix">
  <div class="class1">
    Home
  </div>
  <div class="class2">
    About Us
  </div>
  <div class="class3">
    Privacy
  </div>
</div>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<title>Untitled Document</title>
</head>

<body>
<div style="background-color: red;"><input type="radio" id="radio"></div>
</body>
</html>

a:hover#index {
	background: url("./images/home-red.png") 0 0 no-repeat;
}
a:hover#howto {
    background: url("./images/howtobuild-red.png") 0 0 no-repeat;
}
a:hover#installation {
    background: url("./images/installation-red.png") 0 0 no-repeat;
}
a:hover#design {
    background: url("./images/dande-red.png") 0 0 no-repeat;
}
a:hover#dean {
    background: url("./images/deansblog-red.png") 0 0 no-repeat;
}
a:hover#forum {
    background: url("./images/userforum-red.png") 0 0 no-repeat;
}
a:hover#plan {
    background: url("./images/planbike-red.png") 0 0 no-repeat;
}
a:hover#search {
    background: url("./images/search-red.png") 0 0 no-repeat;
}

a#index, a#design, a#howto, a#installation, a#dean, a#forum, a#plan, a#search   {
	width: 86px;
	height: 27px;
	float: left;
	margin-top:6px;
	position:relative;
	left: 115px;

}

a#index {
	background: url("./images/home-grey.png");
}
a#design {
	background: url("./images/dande-grey.png");
}
a#howto {
	background: url("./images/howtobuild-grey.png");
}
a#installation {
    background: url("./images/installation-grey.png");
}
a#dean {
    background: url("./images/deansblog-grey.png");
}
a#forum {
    background: url("./images/userforum-grey.png");
}
a#plan {
    background: url("./images/planbike-grey.png");
}
a#search {
    background: url("./images/search-grey.png");
}

<ul>
<li>name1<br />address1<br />phone1<br /></li><br />
<li>name2<br />address2<br />phone2<br /></li><br />
<li>name3<br />address3<br />phone3<br /></li><br />
</ul>

#footer {
	background: #49515C url(img/header_right.gif) no-repeat 100%;
	border-bottom: 5px solid #fff;
	border-top: 10px solid #fff;
	text-align: center;	
	color: #fff;
	font-size: 0.8em;
	padding: 10px;
	line-height: 16px;
	clear: both;
	}

<style>
#nameplate {
	top:0px;
	height:1500px;
	z-index:90;
	height:1500px;
	overflow:visible;
	
}

 .img {
	 position:relative;
	display:inherit;
	margin-left:auto;
	margin-right:auto;
 }


</style>
</head>

<body bgcolor="#00FF33" style="margin:0px; padding:0px; max-height:1500px; overflow:visible;">

<div id="nameplate">
<img src="Assets/NamePlate.png" style=" z-index:98; opacity:0.5;" class="img"  /> 

<img src="Assets/SilverPlate.png" style="z-index:95; left:-300px; top: -1000px; width:100px; height:100px;"   class="img"/> 
</div>

<style type="text/css">
<!--

body {
	margin: -10px;
	/*/*/margin: 0; /* */
	padding: 0;
	color: black;
	background: white;
	background-image: url(images/bg%20copy.png);
}

#content {
position:absolute;
	width:200px;
	height:78px;
	z-index:1;
	left: 112px;
	top: 0px;
}

#nav {
	position:absolute;
	border:#000000;
	border-width:thin;
	width:142px;
	height:320px;
	z-index:2;
	left: 123px;
	top: 109px;
}

.style {
background:#A01B1E none repeat scroll 0%;
border:1px solid #000000;

}
#aff {
	position:absolute;
	width:137px;
	height:29px;
	z-index:3;
	left: 123px;
	top: 553px;
}
.style1 {font-size: 12px}
#news1 {
	position:absolute;
	width:200px;
	height:43px;
	z-index:4;
	left: 307px;
	top: 108px;
}
#news2 {
	position:absolute;
	width:200px;
	height:115px;
	z-index:5;
	left: 307px;
	top: 278px;
}
#xtreme {
	position:absolute;
	width:27px;
	height:38px;
	z-index:6;
	left: 860px;
	top: 15px;
}
-->
</style>