You are trying to shut down your PC (Windows XP), but the following error message:
It is now safe to turn off your computer
There is a registry key that can force Windows to automatically power down your computer once it has finished the shutdown process.
Open the registry and go to HKEY_LOCAL_MACHINE/SOFTWARE/Microsoft/Windows NT/CurrentVersion/Winlogon .
. Set the value of the "PowerDownAfterShutdown" key to "1".
Verify that there's no (lengthy) audio file being played during Windows shutdown.
Press and hold the power button to force the shutdown of your PC.
In some cases Windows will display blue screen and then restart your PC. To prevent this from happening: