Problem:
The menu on this website: http://www.sohtanaka.com/web-design/side-navigation-tooltip-popup-bubble/ ran fine in IE. It was quick and worked fine. On my website however, it ran slooow.
Solution:
Look for large images that may be loaded. IE doesn’t seem to handle them very well. The background image for my project was 1196×1150. Pretty large… Gotta adjust for the weakest browsers.