Until someone else can offer advice see if you can turn the computer off using the "shutdown.exe" file in your Windows/System32 directory.
Create a shortcut for it onto your Desktop, instructions here, and see if that works.
Help please. I recently have had trouble turning off my computer when you click on Start and turn off computer and then turn off, nothing happens. This seems to be the only problem I am having. I am running Windows XP Home Edition and IE7. I have to manually press the on/off button to shut down my computer. What can I do. Its a 2 year old Gateway desktop 507GR. This started about 2 weeks ago.
Please help me. Thanks