If you ever get one the i would recommend Ewido Anti-Malware :
Linky:
http://www.ewido.net/en/download/
Its thorough and manages to do the job pretty well plus its free for the trial. Just make sure you never go on a bot site even out of interest and dont download any free bots with "cracks". Keyloggers can come to your PC in many ways so jsut make sure you dont download any files from dodgy sites etc.