Boot your computer in safe mode, disable system restore: right click "my computer" select "properties" go to system restore tab at the top. Then open your C: drive, up top click "tools">folder options>view, then select "show hidden files and folders", then again in your C: drive open the folder "documents and settings" you will see a folder for every user account on your computer go into each of these folders you'll see a "local settings" folder go inside this folder and delete everything in the "temp" folder and everything inside the "temporary internet files" folder, this is where most virses originate, and it will save you time scanning now that your computer has a few thousand less files. once all that is finished empty your recycle bin and run your viruses scanner, make sure you viruses def's are up to date, once the virus scan is finished make a note of which virus or viruses it's found, delete them all then go to www.symantec.com
and do a search for the viruses and look at the removal instructions as you may have to go into the registry and delete a few keys the viruses may have created, you can also download and run ccleaner, do a google search for it. once you install this click the "issues" button and scan for issues, what this does os scans your registry for any invalid keys, and once the virus file is deleted there will be no file associated with the reg key and therefore be invalid and ccleaner should pick it up and delete it.
DT: Abit NF7-Sv2.0, AMD Athalon 3200+ Barton, 1GB PC3200 Kingston Hyper-X RAM, 2x 74GB WD Raptors RAID-0, 256MB XFX 6600GT, gig NIC
NB: Dell Latitude D820, Intel 2GHz Core 2 Duo, 2GB PC2 5300 RAM, Nvidia 120M 512MB video
My Company: Innovative Consulting Group http://www.innovativeITgroup.net