Computer hesitates to shut down

[Hi Ho]

At night when I shut down my computer it resembles trying to start a car. I hit the power button and click shut down then tells me that other users are logged on blah blah blah. I click yes and walk away. I come back a few minutes later and the computer is at the XP welcome screen. I go click shut down and again it tells me that other people are logged on. That tells me that the computer hasn't simply restarted. I walk away again and come back. It's still on. So I hit shut down one last time. This time the computer beeps twice and shuts down in about 3 seconds. This doesn't happen every time but it happens most times I try to shut down my computer. Any suggestions?

[ogrerocks]

what does it do while you're away? Next time try not leaving.

[Hi Ho]

It pretends to shut down. It says "Windows is shutting down", saving settings etc. Then the screen goes black and the welcome screen appears.

[Cricket]

See if anything here helps.

Cricket