then you need to watch Catch me if you Can, The Departed, Blood Diamond, The Aviator, Gangs of New York, and the Beach.
I wasn't a fan till I watched Catch me if you Can - he plays a con-artist and a womanizer
Then he did Aviator, which was pretty decent, you won't like it unless you like Bio-pics, this is where he goes under Martin Scorsese's wing
Gangs of New York was pretty good, but DiCaprio isn't the draw, its Daniel Day Lewis. Another Scorsese flick
The Departed is a fuckin Phoenomenal movie, Again Scorcese
Blood Diamond was pretty good
Watch the Beach, its a Danny Boyle film.
and my bet who the next Batman villain (if Nolan continues)is going to be or replacement of a deceased Batman actors then I would pick DiCaprio, because after seeing the Departed he has the skills, plus he's working with Nolan on Inception.
Sure he had his hearththrob teen magazine days back in 97, but those days are long gone, he's been a character actor for a while, and I don't think i've seen a movie he's in recently that has him with his actual accent. If i could pick any actor he reminds me of its Christopher Walken, i don't know what happened during Catch me if you Can, but the dude rubbed off on him. He totally is the younger version, albeit he is getting better roles younger.