I think this may be a copy, but I don't want to ruin this one if it isn't!
I think the best actor is Will Smith. I just love the emotion he puts into movies such as "Pursuit of Happyness" and "I am Legend." I think if a movie has Will Smith, and he has a gun, than it is going to be a darn good show. Well, Pursuit didn't have a gun, but I Robot did, which was also one of my favorites.
If you go there then you will see the real "Best actors/actress" of all time. But in my opinion, I would have to chose Will Smith for his move "I am Legend" and "Hankcock".