How do I restrict an OS (XP Pro)

[Darvil]

Here is the situation. I built a computer for my sister and the problem is that she keep messing it up. I tell her not to install any programs or go to links that her friends give her but she does it anyway.

Now in the school they have a way to make it so that whenever you reboot the school system, everything is restored to a prebuild stage. Now how do I go about doing the same thing on this computer? It's an XP pro.

Would another way be to reduce permissions and basically restrict the computer from installing new softwares thru IE or others?

Thanks for taking your time to read.

 

[Ryoga]

Make a user account for her and add it to the Guests group. Change the password on your account.

 

[Darvil]

found a program called deep freeze that does the trick.