turn off any file sharing programs you have running and keep them turned off, unshare EVERYTHING, and erase anything you don't have a valid license for or copy of with a program called eraser (its free) and set it to kill, it has a 7 pass DoD wipe and a 35 pass wipe, use the 35 pass one...and quit downloading / sharing illegal content.
From what I've been able to gather they target people who SHARE more so then those who only download, but unless your using some heavy proxy power not even just downloading and not sharing is safe.