Crowder

hey all, its too bad my first post here had to be about this but i cant figure out any way to fix this. i was trying to install a new theme to my computer and the last thing i had to do was add the browserui.dll, and shell32.dll file to the system32 folder. well i did that and i restarted and now at the log in screen i get "this application failed to start because shell32.dll was not found." and i can log in but after that i get the error message again and a black screen. just wanted to know is there anyway i can fix this without having to reinstall vista? i have lots of thing i havent backed up and im sure i can never find again on my hdd and i want to be able to keep it if possible. im not sure if i can find my vista cd now anyway....thanks in advance!