Maintaining public computer labs, or even private computer labs that are used for teaching is a real pain. One thing that may help is PCR-Dist, a program which maintains a master copy of a disk and registry image of a computer workstation and allows the the workstation to be refreshed on demand. This is the ultimate way to nail down the look and feel of a computer and also allow the user to change things without fear of messing something up.
The program is used by many universities. It is for Windows-based computers. An earlier version 1.x can be used with DOS and Windows 3.1 machines.
The program is difficult to use and figure out. In fact, to date I haven’t managed to completely figure it out to the extent that we have it in production, however, I’m reasonably confident that we will be able to have it working. http://www.pyzzo.com