Avast! 9 with Malwarebytes.
In fact someone today asked me to look at their laptop, she claimed it was slow. I did a full AVG 2014 (1 Year licence) scan 0 viruses, I dont trust AVG so I uninstalled it and replace it with Avast Free. After doing a full scan it found 9 viruses, I deleted them, rebooted and it was instantly faster.
Just goes to show you have bad AVG is.