I have a Windows 2000 Server that is freezing up regularly. The freezes occur and all windows close out (as if explorer crashed) except that the mouse is movable. The system does not respond to control alt delete and requires a reboot.
The system will behave normally throughout the week and probably once a week or so (at different times on different days) it will do this. This last time the computers also behaved the same way after the server did it's usual crash.