[Shasown]

Try either of these free remote virus scan and removal tools. Both are from reliable companies and can be trusted. Then look for decent antivirus software. trend offers you a free trial.

While AVG has a free version it is updated later than the fully paid for version.

http://housecall.trendmicro.com/uk/

http://onecare.live.com/site/en-gb/default.htm

They do require you to stay connected to the internet for a while, depending on the size of your hard drive, your connection speed etc. But both will do a good job.