DLL problems

UPDATE BELOW: Explorer.exe won't load now.

Not sure if this is the right forum...

I probably know nothing about computers compared to 99% of you guys, but I was following a poorly written tutorial on how to get a windows skin, which involved changing some .dll files. I was supposed to get ownership of the shell32.dll file and the explorerframe.dll file, which I did (I'm fairly sure. The instructions may have been written for XP which would account for a couple steps I skipped). Anyways, I claimed ownership, and then changed those files to .dll.BAK (backup) as recommended. Then I tried to put in the shell32.dll and explorerframe.dll file that were part of the skin in the system32 folder, but nothing happened. I got frustrated and gave up, but found I could not modify the original .dll files in any way. I tried to 'restore previous versions' (pasting in a previous version from earlier this week), delete the files, rename them back to what they were, regsvr32.exe shell32.dll on cmd prompt, but nothing worked. I am the sole user of this computer (aside from the phantom administrator account), so I should have administrative permission (all the buttons have that shield on them), but I'm confused. I don't really know what those files do, but I'm pretty sure the shell32.dll one is important.

Anyways, I've probably proved how little I know to you, so please help me out. Thanks a lot.

So an update: now my computer can't load explorer.exe (kinda important) without shell32.dll so I need to re-install windows, unless there's some way of loading a boot disk with an .iso file that can fix my registry problems...

Toshiba thought it would be a good idea to have Windows 7 on the Hard Drive, but I can't figure out how to re-install it as of right now.

Help would be much appreciated.