Stupidly changed my registry on my own, will a system restore help me?

A few months ago, I followed an online tutorial to hide my admin account by changing my registry so my mom couldn't get in. Stupidly enough, I kept myself out also. I tried doing a lot of stuff to retrieve it, but nothing would work because the only account I have left is a guest account, therefore, no admin permissions. One thing I think I can still do, though, is a system restoration point, but somehow, my previous restoration point was deleted.
What if, and I'm going out on a limb here, I saved a restoration point off of my friends computer onto a flashdrive and used that for my computer? We have the exact same OS (Windows 7 Premium 64bit). I plan on doing that, then doing a complete system restore back to the factory settings.
Would this work? What precautions would it hold? Like I said, I don't care about my previous data anymore, I just want to take it back to factory settings.
Any help would be INFINITELY appreciated.

EDIT: Okay, after a little bit of research, I discovered that I cant save a system image on a flash drive. I could do it on a DVDR, right?

Hello UglyKid95, and welcome to Seven Forums.

Sorry, but no. Restore points are computer specific, and cannot be used on any other.

You might see if you may be able to boot into Safe Mode or enable the built-in Administrator account at boot to do the factory recovery.

Hope this helps, :)
Shawn