This has no relevance in an XP newsgroup.. a call to the vendor would be
more appropriate..
Do you get the "it is now safe to turn off your computer" message?.. Do you
get a flashing cursor top left of your screen?.. Does it just 'hang' on
'Windows is shutting down'?..
If any of the above, have you tried depressing the power button for
approximately four seconds and releasing it?..