Your system actually
needs most of the junk you tried to delete. You may run into various problems now that system files and folders are missing. I've seen a lot of people run into problems trying to "clean" their computers. What you consider junk, Windows considers necessary. It's best to leave alone files and folders you didn't create.
You can try a program like
Recuva, but things could be ugly regardless since you're dealing with system folders.