but he is actually pretty old as an actor, and IMHO, an actor shouldn't be limited by age. My favorite example of this is Estelle Getty from the Golden Girls. While she was actually the youngest cast member on the show, she played the oldest person, and she played it very well.

But if Leo is as great of an actor as he has been made out to be in the last few years, "Gangs of New York", "Blood Diamond", and the other Scorcese film (sorry, but I haven't seen that movie. Not that interested in it because some guy told me the whole thing).

Leo should be at the point where he could play any age without giving away his age. If he is to be any kind of actor, he should be able to play both Sid Vicious and Beethoven in the same year, like Gary Oldham has done.

Now Gary Oldham would be a good choice.

You know that they are going to cover a large part of his life, and when the same actor is really young, and old, it makes that much better of a movie. Somewhat of a Bildungsroman, only not concentrating on the coming of age.