go to device manager>mouse>properties> "disable". It may be reinstalling because it is activated in BIOS, although mostly it must be detected first.
I have a Dell Dimension XPS T500 with Window 2000.
Just recently when I bring my computer out of hibernation the keyboard will not work and I have to re-boot it to get it back. The keyboard is a Dell QuietKey my mouse is Microsoft Wireless Optical Mouse 2.0. on a USB port. I have tried to uninstall the old PS/2 Port Mouse but when I re-boot the computer it re-installs it again. I have also noticed that in the Events Viewer System Log I get a warning i8042prt EventID 18 which is a problem with the mouse. Could this be connected to the keyboard problem. Hope someone can help, at the moment I just turn the monitor off instead of using Hibernation. The Standby option isn't working properly so I don't use that either.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic