Do you support users who, regardless of what you tell them, insist on logging off or shutting down public computers in common areas? If so, you'll be glad to know that you can disable the Log Off and Turn Off Computer buttons on the Start menu.
Follow these steps:
and select New | DWORD value.
At this point, both the Log Off and Turn Off Computer buttons are still on the Start menu, so click the Log Off button and then log back on.
When you need to shut down the computer, launch the Registry Editor, and change the values to 0.
Note: Editing the registry is risky, so be sure you have a verified backup before saving any changes.