Win2000 Restarting Problem

I installed win 2000 Pro at first I could reboot restart and shut down fine. But for some reason when I try to shut down or restart it will go through the process and freezes right after saying windows shuting down. This will bring me to the fearfull blue screen and I have to shut down manually. Please any Ideas would be greafully
helpfull. I thick it might be a registry problem but I not that fermilure with win2k to go pokeing in the registry. So any help I would appretiate it.

Thank you
Angela