Are you tired of continually fixing someone else's PC because they keep screwing with the registry settings? We can save you some time by disabling that ability all together. ;-)

First log into the person's account and load up regedit (Start -> Run then type regedit and press the ok button), from there follow this path: HKEY_CURRENT_USER -> Software -> Microsoft -> Windows -> CurrentVersion -> Policies. Right click on the Policies folder, create a new key and label it System. Right click on the window on the right and then create a new DWORD value, name it DisableRegistryTools and give it the value 1. Once that's done save, exit and reboot.

Now in the future when the troublemaker tries to open up the registry editor they'll be prompted that the feature has been disabled by the system administrator! This tweak even works on users who have administrative access (but who are not the administrator).