Why can't I turn on my registry editor?

I've been trying to get my realplayer, and video downloader, but after doing a system restore it sort of all went to hell. I've been trying to run regedit.exe but every time I do it says "registry editing has been disabled by your administrator." I've googled my mind into pudding trying to find a fix or how to solve it but it's all just a variation of the same thing and it still results in the same situation 'registry editing has been disabled blah blah blah' anybody know how to fix this? or what i can do??? admittedly i deleted a lot of temp files but have no idea if that has anything to do with it