I noticed when viewing my site with IE 5.0 and Netscape 4.7, the interlacing only seems to work using Netscape. It seems that even thought the gifs I'm using are saved as interlaced, IE waits and loads them compleatly, while Netscape gives you the low resolution preview and build up. Is this normal?
You can see my samples at: http://www.jerseygraphics.com/sampls2k.html
I viewed your page with IE5.0. But I couldn't see any problem. Your intelaced GIFs are OK! They actually interlace. Maybe your IE has some problems.