1) yes. but you'll have to make a mouseover linked div layer before the thumbnail (make sure its not wrapped around the thumbnails) with the dimensions of the thumbnail area, I've added a 'hide all' option below so you can mess around with that
2) yes. just change java script:// to whatever,
(I've included the new stuff below because i cant re-upload to my site right now, ill attach it in a bit.)
<html>
<head>
<style>
#sec1 {position: absolute; top: 40px; left:225px; visibility:hidden; z-index: 100; background-color:Khaki;}
#sec2 {position: absolute; top: 40px; left:225px; visibility:hidden; z-index: 200; background-color:Gainsboro;}
#sec3 {position: absolute; top: 40px; left:225px; visibility:hidden; z-index: 300; background-color:PaleTurquoise;}
#sec4 {position: absolute; top: 40px; left:225px; visibility:hidden; z-index: 400; background-color:Bisque;}
xmp {color:blue; background-color:PowderBlue;}
</style>
<script>
ns4 = (document.layers) ? true:false //required for Functions to work
ie4 = (document.all) ? true:false //required for Functions to work
ng5 = (document.getElementById) ? true:false //required for Functions to work
function hideSec() {
if (ng5) document.getElementById('sec1').style.visibility = "hidden"
else if (ns4) document.sec1.visibility = "hide"
else if (ie4) sec1.style.visibility ="hidden"
if (ng5) document.getElementById('sec2').style.visibility = "hidden"
else if (ns4) document.sec2.visibility = "hide"
else if (ie4) sec2.style.visibility ="hidden"
if (ng5) document.getElementById('sec3').style.visibility = "hidden"
else if (ns4) document.sec3.visibility = "hide"
else if (ie4) sec3.style.visibility ="hidden"
if (ng5) document.getElementById('sec4').style.visibility = "hidden"
else if (ns4) document.sec4.visibility = "hide"
else if (ie4) sec4.style.visibility ="hidden"
}
function showSec(n) {
hideSec();
if (ng5) document.getElementById('sec' + n).style.visibility = "visible";
else if (ns4) document.layers["sec" + n].visibility = "show";
else if (ie4) document.all["sec" + n].style.visibility = "visible";
}
function MM_swapImgRestore() { //v3.0
var i,x,a=document.MM_sr; for(i=0;a&&i<a.length&&(x=a[i])&&x.oSrc;i++) x.src=x.oSrc;
}
function MM_preloadImages() { //v3.0
var d=document; if(d.images){ if(!d.MM_p) d.MM_p=new Array();
var i,j=d.MM_p.length,a=MM_preloadImages.arguments; for(i=0; i<a.length; i++)
if (a[i].indexOf("#")!=0){ d.MM_p[j]=new Image; d.MM_p[j++].src=a[i];}}
}
function MM_findObj(n, d) { //v4.01
var p,i,x; if(!d) d=document; if((p=n.indexOf("?"))>0&&parent.frames.length) {
d=parent.frames[n.substring(p+1)].document; n=n.substring(0,p);}
if(!(x=d[n])&&d.all) x=d.all[n]; for (i=0;!x&&i<d.forms.length;i++) x=d.forms[i][n];
for(i=0;!x&&d.layers&&i<d.layers.length;i++) x=MM_findObj(n,d.layers[i].document);
if(!x && d.getElementById) x=d.getElementById(n); return x;
}
function MM_swapImage() { //v3.0
var i,j=0,x,a=MM_swapImage.arguments; document.MM_sr=new Array; for(i=0;i<(a.length-2);i+=3)
if ((x=MM_findObj(a[i]))!=null){document.MM_sr[j++]=x; if(!x.oSrc) x.oSrc=x.src; x.src=a[i+2];}
}
function hideAllSec(n) {
if (ng5) document.getElementById('sec' + n).style.visibility = "hidden";
else if (ns4) document.layers["sec" + n].visibility = "hide";
else if (ie4) document.all["sec" + n].style.visibility = "hidden";
}
</script>
</head>
<body>
<div id="sec1">1</div>
<div id="sec2">2</div>
<div id="sec3">3</div>
<div id="sec4">4</div>
<a href="java script://" onMouseOver="hideAllSec(1),hideAllSec(2),hideAllSec(3),hideAllSec(4)">Hide All</a>
<a href="http://google.ca/" onMouseOver="showSec(1)">Show Layer 1</a>
<a href="java script://" onMouseOver="showSec(2)">Show Layer 2</a>
<a href="java script://" onMouseOver="showSec(3)">Show Layer 3</a>
<a href="java script://" onMouseOver="showSec(4)">Show Layer 4</a>
</body>
</html>