Sounds bad...you most likely will have to format the whole drive and reinstall windows as if it was a bad virus could of destroyed everything.
What errors does it give you when you run the antivirus tools from UBCD? Could you please write them down?
At this point if you cant even run antivirus software on the hd because you are getting error probably relating to bad disk..I would DL knoppix
pick a mirror and dl the latest iso, burn it to cd and boot from it and Back-up >ALL< data you can and format the whole HD with a complete, NOT quick format, and then reinstall windows.
You really really need to be careful with emails. Never open one you dont know who its from.
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