glytch

This might not be as easy as it should be, but it's not very hard, just tedius. The only way I know of doing things like that is go to start->run then type mmc. This will bring up the Microsoft Management Console. From there, choose file->add/remove snap-in. Once at that screen, hit add and a list will pop up. From there you can play around with all the settings you would like to have on these new computers. The ones I'd check out first are Group Policy, Users and Groups, and Security Configuration and Analysis. The group policy will allow you to disable just about everything on your computer that you don't want the customers to use, and unless they're pretty computer knowledgable, they won't be able to undo it.

Anyway, I hope this is what you're looking for.

EDIT: Also, look into disk quotas for limiting the disk space they can use.

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