HTML - Background Issues!

ok hiya im wondering if you can sort my problem out? i recently set up a forum
for a gaming clan and i have thought of a design that i like but there is a problem....

i have designed a background which can be seen he
http://img177.imageshack.us/img177/3...imgcopylm8.jpg
btw the middle isnt orange only for thsi sample i made.

the only problem is it works perfectly for the resolution of my screen (1280x800) but not on my pc which is 1024x768. because of this it throws the whole of the forum out of line on a different resolution screen. the code for this background is in the css stylesheet but i was wondering if there was a code i could use that would display a different picture depending on the screen resolution i.e. i could rado the image several times to fit each screen resolution. if not gthen is there anyway of haveing a background with those 2 bits on the sides that will work in all of the resolutions??

his is how i want my site to look and how the sides should be and this is how it shows at 1280x800:



this is perfect until you view it at any other resolution.lol

like this resolution(1024x768):



is there anyway of making it look like the top on all of the resoltuions?



the link to the site i want to use it on is:

www.gusoldiers.forumn.net


here is the cxode im currently using (for this part):

* {
margin: 0px;
padding: 0px;

}
html {
background-color: #000001;
font-size: 100%;
height: 100%;
}
#min-width {
min-width: 750px;
}

body { background-color: #cce3f3;

background: url('http://img177.imageshack.us/img177/339/backgroundimgcopylm8.jpg') repeat-x;
background-attachment: fixed;
font-family: "Lucida Grande", Verdana, Helvetica, Arial, sans-serif;
font-size: 62.5%; /* This sets the default font size to be equivalent to 10px */
margin: 0px 0px 0px 0px;
padding: 0px;
border-color: #862121;
border-width: 0px 0px 0px 0px;
border-style: solid;
}

{
font-size: 10px;
height: auto;
padding: 10px 0px;
scrollbar-face-color: #;
scrollbar-highlight-color: #;
scrollbar-shadow-color: #;
scrollbar-3dlight-color: #;
scrollbar-arrow-color: #;
scrollbar-track-color: #;
scrollbar-darkshadow-color: #;
}
* html .conteneur_minwidth_IE {
/* Hack IE min-width */
padding-left: 750px;
}
* html .conteneur_container_IE {
/* Hack IE min-width */
margin-left: -750px;
position: relative;
}
* html .conteneur_minwidth_IE, * html .conteneur_container_IE, * html .conteneur_layout_IE {
/* Hack IE min-width */
height: 1px;
}


#wrap {
width: 80%;
margin: 0px auto;
background-color: #1a1a1a;
background-image: url("");
background-repeat: repeat-x;
background-attachment: fixed;
border-color: #46494b;
border-width: 0px 0px 0px 0px;
border-style: solid;

padding: 5px;
}


#wrapnav {
width: 800%;
margin: 0;
background-color: #ECECEC;
border-width: 1px;
border-style: solid;
border-color: #A9B8C2;