Oh, The Old Gray Whore, She Ain't What She Used To Be

Can anyone tell me how to fix my computer? It was filled with viruses, thanks to LimeWire, a music file sharing hellhole (kids these days -- a big bow to my oldest daughter), and though I deleted the viruses, my computer is still crashing, and I can't use Word (I get a "This application has failed to start because Ms.dll was not found. Re-installing the application may fix this problem" message) or anything else on this machine. Tried to used Add/Delete Programs (to get rid of LimeWire) for instance, but it's as if it's dead. Same thing when I try to do System Restore. Nothing works. And the colors are weird when I'm in My Computer, particularly the sidebar -- the background is black.

Also, the other hellhole, Blogger, has been on the fritz, as usual, and I apologize to those of you who have had trouble leaving comments -- today, Blogger is still shit, and you may have more trouble with comments. I'd be ever so grateful if you'd e-mail me (it's in my profile) with any suggestions as to what I can do to fix my old whore. Thank you.

UPDATE: All fixed. Had to do a complete system recovery, reinstall Windows, yaddayaddadingdong, and I drank many, many beers during the process. Thanks to all who took time out of their day to e-mail me or comment -- you helped, and you rock!

ANOTHER UPDATE (3/21): Not it's not. You all still rock, but my machine still sucks. Boo.