User Profile Hive Cleanup Service
Brief Description
A service to help with slow log off and unreconciled profile problems.
Overview
The User Profile Hive Cleanup service helps to ensure user sessions are completely terminated when a user logs off. System processes and applications occasionally maintain connections to registry keys in the user profile after a user logs off. In those cases the user session is prevented from completely ending.
To accomplish this the service monitors for logged off users that still have registry hives loaded. When that happens the service determines which application have handles opened to the hives and releases them. It logs the application name and what registry keys were left open. After this the system finishes unloading the profile.
(the link above)
If I am not mistaken you don't run it. It just makes sure you are logged off of sites as you go along.
Why windows takes solong to shut down.
Once you run the setup wizard it will look like the installer did nothing. If you open up your services list (Click start, then run and type services.msc now click ok), you will see that a new service is running in the background:
The idea of this program is to reclaim resources when a task is finished (memory, handles, etc). It accomplishes this by monitoring for users to log off and verifying that unused resources are reclaimed. This approach is superior as it works for any known reason that profiles do not unload and also will keep working to address new unknown issues.
Now when you go to shutdown, logoff or restart it will happen within seconds. Instead of minutes.
http://www.intelliadmin.com/blog/2006/07/why-windows-takes-so-long-to-shut-down.html
I have heard of NOD 32, but why would you have it disabled?