Hi CSR,

Have you looked at "Deepfreeze" by Faronics software?

http://www.faronics.com/

It doesn't do exactly as you are asking, but might be of interest as an additional or alternative approach? Basically it stores the authorised setup and writes it back on reboot, thus undoing any changes that might have been made in the last session.

It costs, but is an easy solution. I believe that they give discounts for .edu users