Sounds like you're running into a glitch in the whole fast user switching feature of XP. Windows was never really designed to be a multi-user system, and trying to graft such a feature on comes with it's share of problems.
Probably your best bet is to hope that it's an interaction with your video drivers, and that updating them will help. If that doesn't work, you're probably pretty much SOL.
I have two accounts of my Windows XP machine. If I turn on the computer and log into my personal account, everything works fine. If my girlfriend switches to her account at all, afterwards, on my account, every window/program that is maximized is just barely cut off at the bottom of the screen. It wouldn't be such a big deal, but this means I can't see my status bar in my web browser and other important information at the bottom of other programs. Of course, everything is visible when "restored down", but I like my windows/programs to be maximized. Please help if you are knowledgable! Thanks!

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