Loading Personal Settings (for 5 min?)

Lately, all of the computers in my domain have been having issues with logging in. They’ll all get stuck on “Loading Personal Settings”. Not consistently, and not the same computer each time. I don’t know where to begin, as it is such an inconsistent problem.
Can anyone give me some ideas?

Here’s a brief overview of my network:
32 Windows 2000 PC’s on a 2000 Domain (tweaked all over by previous IS Manager)
I recently installed a new Exchange Server and File Server (and web server) on a DIFFERENT domain, running on the same network.

Could this new domain be goofing anything up?

Any ideas on where to start would be greatly appreciated!!

Traci
San Francisco, CA