Oh i can see why you say IE is out dated, cos it is!
Ive looked at the code, and nothings wrong with it!
I tested the page in IE (for mac tho) and it works fine!
One thing you may want to add to the image maps to stop IE and other browsers putting a border around the image link in the menu when its selected:
onFocus="this.blur()"
this tells the browser not to focus in on the selected item so that those stupid borders dont show and dont mess up the whole site impact!
As well as that, it try to use a more IE friendly layout (i no everyone hates IE, i use firefox) but the majority of people are still on IE and when they come to the site and see things diff! Get what i mean?
Oh before i forget, allowtransparency="true" never works on IE!! be careful!
But back to the gallery, if it still doesnt want to work, you might want to try opening it in a new window. Or slicing up your menu instead of using image maps because that is then true href links, get what i mean?
all the best!