It has happen to most of us, and if it hasn't "just keep living" as my mother would say. The dreaded virus on your PC. It was getting a virus on my laptop a few years ago they lead me down a path of becoming a little more tech savvy. I covered how to enter safe boot mode in an earlier post if you find yourself in this position, but today I'm focusing on something simple.
Most of the viruses I've seen in 2010 try to get you to buy their software to remove the program or attack any accounts you have not logged out of. Logging out your account when you finish with them is extremely important, or even when just surfing the web. These virus programs will spam your email address book, or post things to your Facebook wall or whatever social network you may be using. In either case your friends are not going to like receiving spam or links that open to porn on their Facebook wall.
To stay protected against these viruses I recommend Microsoft Security Essentials. Its free, and has received high reviews since its release. Warning though, if your using a unlicensed copy of windows it want work because it has to validate your machine before installing the software. So remember, logging out of your accounts when your done will stop some of the damage a virus can cause.