I think good advice for all would be never download anything from anyone you don't "know"... the problem is that viruses sometimes automatically send from people that we do "know" and that's what makes the new bad ones so affective at spreading :(
As a computer guy I don't download anything from anyone unless it's work related, and a pdf or a jpg... movies, power point presentations, mp3s, etc just get deleted.
A good virus scan software like AVG is something else I suggest as well as windows defender
Ok enough geeeek talk! heh!