Hi, I am having problems with my Dell Dimension 9200.

Since last week I can't turn my computer off from the start menu, shut down.
The message "Logging off" sometimes appears, but then nothing happens. Or
sometimes when I click Shut down nothing happens and I need to shut it down
from the main power button.

When just logging off the computer remains on the logging off screen.

My itunes is not working. Even though I can see it on the task manager, the
program doesn't start up.

I just installed SP1 for my Vista Home Premium

I installed the new free AVG 8.0

Please help, it's driving me mad and my wife is not happy ;(

Thanks
--
Canek