If you don't want to run screensaver then another way can be by running a scheduled task which runs after 10 minutes of idle time. The task to run would be
Code:
%windir%\system32\rundll32.exe user32.dll, LockWorkStation
As far as Puja's comment about the way the question is asked, I must say that a similar situation arose a few months ago on Linux Users Group, Delhi as well. We all were told to read the following document.
http://www.tldp.org/HOWTO/Encourage-Women-Linux-HOWTO/
Even though it is related to Linux and has been written by LinuxChix group but it still is very relevant to the general technology environment.