Create separate system user profiles for them: Mom, Sisters, Dad or Renegade and Family. Set easy to remember passwords. Disable os autologin (so they will have to enter their passwords). These Users (not you) should belong to Restricted Users group (not power or administrators), so they couldn't install any dangerous software, or change whole system enviroment. NT is a multiuser os, afterall.
I have some problems with internet connection, so new exciting details about your system will wait until monday
Good luck with your struggle for clean system.
Re: How do I turn off Overclocking??
Threaded Mode