If I'm getting you, you want to change the content of a part of the page when you click a link. If so you'll probably want Ajax, although you could use an iframe, or even a page reload with url parameters.
An image map is just a glorified bunch of image links, so it/they should work as stated by Menster. If an imagemap link doesn't work, be sure to check the html syntax - all the t's crossed and all the i's dotted!
echo '<a href="http://mydomain.com">My domain</a>' This bit may cause problems - I didn't realise that you were passing this as a parameter in a js call. You need to encode the tag, or better still, just pass the url string (mydomain.com):
Like this: ... onclick="changeDivContent('scriptVars1','<?php echo $url;?>','<?php echo $label;?>');" ... and change this to:
function changeDivContent( nameOfDiv, newContent, newLabel )
var div = document.getElementById( nameOfDiv );
if( div )
div.innerText = '<a href="http://' + newContent + '">' + newLabel + '</a>' ;