Windows sometimes will not shut down properly, you try to shutdown your system and nothing happens for a while.  Then a window appears telling you that a task will not shut down and you are prompted to either press "End Now", or you can wait for Windows to try and end it itself.

You can avoid that hassle by making a simple registry tweak.  Please remember that it is recommended that before any changes are made to your registry, you back it up first!  The registry tweak is as below:-

1. Click on your "Start" button and click on "Run..."
2. In the window type "regedit" and press "OK"
3. Double click on "HKEY_USERS"
4. Double click on ".DEFAULT"
5. Double click on "Control Panel"
6. Click on "Desktop"
7. You should now be at "HKEY_USERS\.DEFAULT\Control Panel\Desktop"
8. From the right hand panel double click on "AutoEndTasks"
9. Change the Value data from 0 to 1 and press "OK"
10. Close the Registry Editor window and reboot your machine

Now hung processes will end automatically when you shutdown or reboot your computer.  Please be aware that if a process is forced to end, whether manually or automatically then you are at risk of possible data loss, depending on the process concerned.