My guess is you are using IE 5.x for the mac? It's a dog and there is no way to fix it. It's equally bad (and BUGGY) on OS 10.x.
IE 5 on PC would load one of my pages in 2-3 seconds that IE 5 on Mac (even on a fast mac) would take 20-30 seconds to load. Dialup on a PC was significantly faster than a Mac on broadband.
I recommend that my Mac sys9 users use Netscape 7. Netscape 7 is about as fast as IE on the PC...7-12 times faster than IE 5 for Mac.
Free download, etc. VERY fast, even faster than safari if you use compressed output.