Tips & Tricks
By default, Windows waits for five seconds to allow time for any hung applications to be closed properly as you shut down your computer. You can change this hanging time with a registry edit.
Browse to HKEY_CURRENT_USER\Control Panel\Desktop and select the string entry called ‘HungApp Timeout’. If you’re using Vista, you’ll need to create this entry. Right-click this and choose ‘Modify’.
The number is in milliseconds, so the default of 5,000 is a wait of five seconds. Simply choose a lower number to shorten the wait time.