A commonly question asked is: can I automatically log off workstations after so many minutes of inactivity?
Well, through Group Policy you can force to lock down a workstation via a password protected screensaver, but not to log it off. The GPO settings for locking down a workstation via screensaver can be found at:
Administrative templates\control panel\display\password protect the screen saver and screen saver timeout.
You can also use the WinExit.scr utility to implement the screen saver lockdown method. Check it out here:
Finally, there are third party vendors that may provide a solution to that problem. One third party program is Fortress-NT/2000, available via the following link: http://www.whitehatinc.com/w2ktools/fortress/ . The vendor claims that this program/utility can enforce log off times on client machines. This is not a Microsoft product, and we cannot state how well, or if it does what it advertises to do.