[AT] OT - BIG computer problem

[msm10301 at juno.com]

Hi All,
I have a very sick computer at home, and I could use some advice on the best way to fix it. I started Saturday, when I opened NAV 2004 and tried to run a scan which it had as overdue. When I clicked the "scan now" button, the computer told me that this user didn't have the priviledges to run this scan. I linked to Symantec's site, and followed their fix, but it did nothing. I have never set up users on my system, and have had it for 4 years. Since I couldn't use Norton, I down loaded and installed AVG 6.0 from Grisoft, and Zonealarm. I had AVG run a scan and it found a virus, which it called a trojan horse scedA. It said it couldn't heal the file, and that it would need to be deleted. I ran the scan again, and it found the same virus in another file. I then encountered an error and had to restart my computer. When it booted up, I had two errors both of which read " Validation failed for C:\windows\system\vsinit.dll. Most of my icons are missing, and the "Start" button is inoperable. Since I couldn't use "Start", I couldn't get to system restore to try that option. I finally found system restore in the C drive folder, but it won't run. Bottom line is my computer will do nothing and many things simply will not run. I managed to burn copies of things I wanted to save. My thought was to format C drive and reinstall windows, but I'm in uncharted waters here, and wanted some input before I tried that. Any help would be appreciated.

Thanks,
Mike