<div id="WIND" style="position:absolute; width:200px; height:200px; left:120px; top:120px; border : solid 1px red">
Тест
</div>
 
<script language="JavaScript1.2">
// Зона за которую можно таскать
var x = 0;
var y = 0;
var w = 100;
var h = 100;
 
document.onmousemove = MouseEvent;
document.onmousedown = MousePress;
document.onmouseup = MouseUnPress;
 
var browser = navigator.appName;
var ver = parseInt(navigator.appVersion);
 
if (browser != "Microsoft Internet Explorer")
{
    document.captureEvents(Event.MOUSEDOWN | Event.MOUSEUP);
    document.captureEvents(Event.MOUSEMOVE);
    obj = document.getElementById('WIND');
}
else
{
    document.onselectstart = checkEl;
    document.ondragstart = checkEl;
    obj = document.all.item('WIND');
}
 
function checkEl()
{
   return false;  
}
 
var pressflag = false;
var oldcursx, oldcursy;
var firstflag = true;
var flag = false;
 
function MouseEvent(ev)
{
    windx = parseInt(obj.style.left);
    windy = parseInt(obj.style.top);
    cursx = (browser == "Microsoft Internet Explorer") ? event.clientX : ev.clientX;
    cursy = (browser == "Microsoft Internet Explorer") ? event.clientY : ev.clientY;
 
    if(firstflag)
    {
        oldcursx = cursx;
        oldcursy = cursy;
        firstflag = false;
    }
 
    if (flag) {
        obj.style.left = windx + cursx - oldcursx;
        obj.style.top =  windy + cursy - oldcursy;
    }
    oldcursx = cursx;
    oldcursy = cursy;
}
 
function MousePress()
{
    if ( (cursx > windx+x) &&
         (cursy > windy+y) &&
         (cursx < windx+x+w) &&
         (cursy < windy+y+h) )  
    {
        obj.style.cursor = "move";
        flag = true;
    }
}
 
function MouseUnPress()
{
    if (flag)
    {
        pressflag = flag = false;
        obj.style.cursor = "auto";
    }
}
</script>