You might want to create a new hardware profile and shutdown every service you don't need. Once that's done, create a new user, and apply said hardware profile so no unneeded services are running.
This is a good reference point:
http://www.editthis.info/sonar/Optimizing_Your_DAW
This is something that's urked me for a while now. Why Microsoft hasn't figured out a way to allow SCW to shutdown services and processes you don't need when you create a new profile for a DAW is beyond me. They should do the same thing with Vista and server 2008 so that when you're installing their os for a DAW, it knows that you'll never need things like wuau services, firewall, etc.
Jimmy
