Hi DB6,
Firstly any anti virus software is only any use if its bang upto date, in the office we update at least daily.
If it is not up to date it gives you a false sense of security - in a way you are better with no AV rather than an out of date AV pack as at least then you assume everything is infected!
Ok now a suggestion visit
www.sophos.co.uk or
www.sophos.com
Register for a free trial and then follow the instructions to check for viri then disinfect. I think on a trial you can even call tech support - open 24 / 7.
Sophos is not the cheapest ( I think about £80 per year) - but it works, it won't even let you open an infected file, email or web page.
Good luck!
P.S. Moderators - am I breaking the rules by naming the product?
After you get rid of the virus
windowsupdate.com and download all the latest bug fixes for windows, outlook / outlook express etc. (Assuming that you do not already do this! - excuse me if you do!)
This will close a lot of the security holes that let the viri infect your machine and spread to other machines.
It also means you need to sign all sorts of new (nasty!) user agreements.