Shared Computer Toolkit WDP (Score 3, Informative)

It's free, and designed for XP and schools and libraries. It's pretty easy to install and configure too, if you know how to repartition your drive using Partition Magic. I use it, so reply if you want hints on getting it to work. You need WPA, and Hive cleanup service installed for it to go. It lets AV programs update, and Grisoft gave me a script to make it work with the SCT Windows Desktop Protection. Just reboot, and changes are gone, unless you save them first. Have the computers update overnight, because it doesn't work when people need to use the computer.