Step 1: Add the following script into the <HEAD> section of your page:

<script>

var dragapproved=false
var minrestore=0
var initialwidth,initialheight
var ie5=document.all&&document.getElementById
var ns6=document.getElementById&&!document.all

function drag_drop(e){
if (ie5&&dragapproved&&event.button==1){
document.getElementById("dwindow").style.left=tempx+event.clientX-offsetx
document.getElementById("dwindow").style.top=tempy+event.clientY-offsety
}
else if (ns6&&dragapproved){
document.getElementById("dwindow").style.left=tempx+e.clientX-offsetx
document.getElementById("dwindow").style.top=tempy+e.clientY-offsety
}
}

function initializedrag(e){
offsetx=ie5? event.clientX : e.clientX
offsety=ie5? event.clientY : e.clientY
if (ie5)
document.getElementById("saver").style.display=''

tempx=parseInt(document.getElementById("dwindow").style.left)
tempy=parseInt(document.getElementById("dwindow").style.top)

dragapproved=true
document.onmousemove=drag_drop
}

function loadwindow(url,width,height){
if (!ie5&&!ns6)
window.open(url,"","width=width,height=height,scrollbars=1")
else{
document.getElementById("dwindow").style.display=''
document.getElementById("dwindow").style.width=initialwidth=width
document.getElementById("dwindow").style.height=initialheight=height
document.getElementById("dwindow").style.left=30
document.getElementById("dwindow").style.top=ns6? window.pageYOffset*1+30 : document.body.scrollTop*1+30
document.getElementById("cframe").src=url
}
}

function maximize(){
if (minrestore==0){
minrestore=1 //maximize window
document.getElementById("maxname").setAttribute("src","restore.gif")
document.getElementById("dwindow").style.width=ns6? window.innerWidth-20 : document.body.clientWidth
document.getElementById("dwindow").style.height=ns6? window.innerHeight-20 : document.body.clientHeight
}
else{
minrestore=0 //restore window
document.getElementById("maxname").setAttribute("src","max.gif")
document.getElementById("dwindow").style.width=initialwidth
document.getElementById("dwindow").style.height=initialheight
}
document.getElementById("dwindow").style.left=ns6? window.pageXOffset : document.body.scrollLeft
document.getElementById("dwindow").style.top=ns6? window.pageYOffset : document.body.scrollTop
}

function closeit(){
document.getElementById("dwindow").style.display="none"
}

if (ie5||ns6)
document.onmouseup=new Function("dragapproved=false;document.onmousemove=null;document.getElementById('saver').style.display='none'")

</script>


Step 2: Add the below to the <BODY> section, preferably at the end of the page:


<div id="dwindow" style="position:absolute;background-color:navy;cursor:hand;left:0;top:0;display:none" onMousedown="initializedrag(event)" onSelectStart="return false">
<div align="right"><img src="max.gif" id="maxname" onClick="maximize()"><img src="close.gif" onClick="closeit()"></div>
<iframe id="cframe" src="" width=100% height=100%></iframe>
<div id="saver" style="width:100%;height:100%;position:absolute;left:0;top:0;display:none"></div>
</div>

<script>
//Use below code to load DHTML Window as page loads 
if (ns6) window.onload=new Function('loadwindow("http://www.geocities.com",600,400)')
else
loadwindow("http://www.geocities.com",600,400)
</script>

<!--Use below code to load DHTML window via link-->
<a href="javascript:loadwindow('http://www.geocities.com',600,400)">Geocities</a>


Step 3: Finally, the script uses 3 images (the "close", "maximize", and "restore" buttons). 
and upload them to your webpage directory
