JavaScript - Menu Which Shows And Hides Divs

function swapvideo(w,h,url) {
	document.getElementById('video_pholder').style.display='none';
	document.getElementById('video_code').innerHTML="<iframe src='"+url+"' width='"+w+"' height='"+h+"' frameborder='0' webkitAllowFullScreen allowFullScreen></iframe>";
	document.getElementById('video_code').style.display='block';
}

<div id="video_pholder"><a href="" onclick="swapvideo('700','394','http://player.vimeo.com/video/30620364?title=0&amp;byline=0&amp;portrait=0&amp;color=FFFFFF&amp;autoplay=1'); return false;">
	<img src="image.jpg" width="700" height="393" /></a>
</div>
<div id="video_code" style="display:none;"></div>

<script type="text/javascript">
function showstuff(element){
        if(document.getElementById(element).style.display = 'block')
                  {
                        document.getElementById(have).style.visibility="block";
                        document.getElementById(look).style.visibility="none";
                  }
        else if(document.getElementById(element).style.visibility = 'block')
                  {
                        document.getElementById(look).style.visibility="block";
                        document.getElementById(have).style.visibility="none";
                  }
}
</script>

<select name="type" onchange="showstuff(this.value);">
          <option value="look">Look</option>
          <option value="have">Have</option>
</select>
<div id="have" style="display:block;">Have</div>
<div id="look" style="display:none;">Look</div>

function typeoflisting() {

	var selectform = document.getElementById('propertytype');
	
	if (selectform.options[selectedIndex].value == "sell") {
		document.getElementById('per_week').style.display = 'none';
		document.getElementById('bond').style.display = 'none';
	}
	else {
		document.getElementById('per_week').style.display = 'block';
		document.getElementById('bond').style.display = 'block';
	}	
}

<select id="propertytype" name="propertytype" class="select" onchange="typeoflisting()">	
	<option value="lease">I'd like to lease a property to tenants</option>
	<option value="sell">I'd like to sell a property</option>
	<option value="share">I'd like to share a property</option>
</select>

<div id="per_week" style="float: left;"> per week</div>

<div style="float: left; padding: 20px 20px 0px 0px;" id="bond">
<h3>Bond</h3>
<input type="text" class="text" value="$"/>
</div>

var thumbProportion = .17 // thumbnails are 32% of their full size;
	var IE = false; 
	if (navigator.appName == "Microsoft Internet Explorer"){IE = true;}

	function swapImg(nImg,nSwapImgClass,nFullSizeImg){		
		
		var thumbImg = nImg;
		var thumbImgAlt = thumbImg.alt;
		var origFullWidth = nFullSizeImg.width; 		
		var origFullHeight = nFullSizeImg.height;		
		var tempImgHolder = nFullSizeImg.src;
		var origFullAlt = nFullSizeImg.alt;
		nFullSizeImg.src = thumbImg.src;
		thumbImg.src = tempImgHolder;
		nSwapImgClass.style.width = nFullSizeImg.width + "px";
		thumbImg.style.width =  Math.round(origFullWidth * thumbProportion) + "px";	
		thumbImg.style.height =  Math.round(origFullHeight * thumbProportion) + "px";	
		thumbImg.alt = origFullAlt;
		thumbImg.title = origFullAlt;
		nFullSizeImg.alt = thumbImgAlt;
		nFullSizeImg.title = thumbImgAlt;
		nCaption.firstChild.data = thumbImgAlt;
	}

	function init(){

		var nImg = document.getElementById('fullSizeContainer');
		var fullSizeImg = nImg.getElementsByTagName('img')[0];
		nCaption = nImg.getElementsByTagName('div')[0];		
		IE ? nRule = document.styleSheets[3].rules : nRule = document.styleSheets[3].cssRules;
		for (i=0; i<nRule.length; i++)
			{
		 	 if (nRule[i].selectorText == ".swapImg")
				{	
				 var swapImgClass = nRule[i];
				 nRule[i].style.width = fullSizeImg.width + "px";				 
				}		
			}	
		var nGallery = document.getElementById("photoGallery").getElementsByTagName("a");
		for (i=0; i<nGallery.length; i++)
			{
			 nGallery[i].onclick = function()
				{
			 	 swapImg(this.firstChild,swapImgClass,fullSizeImg);
			 	 return false;
				}			
		 	nGallery[i].href = "#";			
			}	
	}

	IE ? attachEvent('onload', init, false) : addEventListener('load', init, false);

<div><!-- start of div2 -->
	<div class="floatleft"><a href="#" id="textbox-show" class="showLink" onclick="showHide('textbox');return false;">Show more</a>
	</div>
			<div><!-- start of div3 -->
				<div id="textbox" class="more">
					<div class="formtitles">Show more&nbsp;&nbsp;<a href="#" id="textbox-hide" class="hideLink" onclick="showHide('textbox');return false;">Hide this content</a>
					</div>

					<div>

						<div class="containercolour3">
							<div class="rtopcolour3">
								<div class="r1"></div><div class="r2"></div><div class="r3"></div><div class="r4"></div>
							</div>
			
							<div class="formspacer">Hidden text</div>
			
							<div class="rbottomcolour3">
								<div class="r4"></div><div class="r3"></div><div class="r2"></div><div class="r1"></div>
							</div>
						</div>

					</div>

			</div>
			<!-- end of div3 --></div>
<!-- end of div2 --></div>

<SCRIPT type="text/javascript">
<!--
function displayEntries () {
var sfirst = document.frmStudentInfo.textSfirst.value;
var smi = document.frmStudentInfo.textSmi.value;
var slast = document.frmStudentInfo.textSlast.value;
var sadd = document.frmStudentInfo.textSadd.value;
var scity = document.frmStudentInfo.textScity.value;
var sstate = document.frmStudenInfo.textSstate.value;
var szip = document.frmStudentInfo.textSzip.value;
var sphone = document.frmStudentInfo.textSphone.value;
var sdob = document.frmStudentInfo.textSdob.value;

window.alert('sfirst' + 'smi' + 'slast' + '\n' +
'sadd' + '\n' +
'scity' + 'sstate' + 'szip' + '\n' +
'sphone' + '\n' +
'sdob');
}
//-->
</SCRIPT>

    <td><input type="button" name="cmdUpdate" value="Update" onClick="displayEntries();"></td>

// snowscript part 3:   Show the script between 19-31 Dec and 1 Jan 

var date = new Date();
var d  = date.getDate();
var m = date.getMonth() + 1;
dm = d + m;

if  (m = 12) 
{
   if (d > 18)
   { document.write('<script src="/scripts/snowlinkswitch.js" type="text/javascript" id="snow"></script>');   
   }
   else 
   { 
   document.write('');
   }
}
else if (dm == 1,1)
  {
  document.write('<script src="/scripts/snowlinkswitch.js" type="text/javascript"></script>');
  }
else
  {
  document.write('');
  }

function myhref(){
    document.getElementById('myAnchor').innerHTML="please let it snow!";
    document.getElementById('myAnchor').href=location.href;
    document.getElementById('myAnchor').title="let it snow! let it snow!";  
    document.getElementById('myAnchor').onclick="location.reload(); startstop('spanstyle'); return false;";
}

// 

document.write ('<div id="snowlinks"><img src="/images/snow3aa.gif" width="11" height="11" border="0" alt="*"> <a id="myAnchor" href="" onclick="myhref();hidesnow(); return false;" title="please make it stop snowing!">please make it stop snowing!<\/a> <img src="/images/snow3aa.gif" width="11" height="11" border="0" alt="*"></div> ');

 <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>

<script type="text/javascript" src="fadeslideshow.js">

/***********************************************
* Ultimate Fade In Slideshow v2.0- (c) Dynamic Drive DHTML code library (www.dynamicdrive.com)
* This notice MUST stay intact for legal use
* Visit Dynamic Drive at http://www.dynamicdrive.com/ for this script and 100s more
***********************************************/

</script>

<script type="text/javascript">

var mygallery=new fadeSlideShow({
	wrapperid: "fadeshow1", //ID of blank DIV on page to house Slideshow
	dimensions: [1024, 400], //width/height of gallery in pixels. Should reflect dimensions of largest image
	imagearray: [
		["http://www.kristynaswebpages.com/falcon_1.jpg", "", "", "The A Control Room is blah blah blah"],
		["http://www.kristynaswebpages.com/falcon_2.jpg", "", "", "The A Control Room is blah blah blah"],
		["http://www.kristynaswebpages.com/falcon_3.jpg"], 
		["http://www.kristynaswebpages.com/falcon_4.jpg", "", "", "The A Control Room is blah blah blah"] //<--no trailing comma after very last image element!
	],
	displaymode: {type:'auto', pause:2500, cycles:0, wraparound:false},
	persist: false, //remember last viewed slide and recall within same session?
	fadeduration: 500, //transition duration (milliseconds)
	descreveal: "ondemand",
	togglerid: ""
})


</script>