i have to say bobby's best role was travis bickle in taxi driver. IT WAS CLASSIC!!!!!!! "you talkin to me" was born and is now his most famous line.
If i had to pick a second best it would have to be
either johnny boy (mean streets) or Godfather
Part 2.
Skinhead

P.S. IM A TRADSKIN NOT A FUCKING NAZI!!!!!!!! TRUE SKINS ARENT EVEN NAZIS!!!!!!