Personally for me this is one of the toughest choices of this round. Both movies I found myself enjoying, and I watched both films again. Also both movies have two of my favorite actress of all time(Swank & Thurman).
Million Dollar Baby was a great movie that made me a little teary eyed. It pulls at your heart string(or mine atleast)It is written great, acted great, and Clint's Direction proves why he won the best director award. I just really enjoyed the story of this film and the way the actors(espicially Swank)brought their characters to a whole new level.
Now Kill Bill Vol.2 is also a personal favortie of mine. The movie is able to mix action, drama, and even some comedy into the film. Uma Thurman plays the assasian out for revenge amazingly and when you learn about the baby and stuff it is all wonderfully played out. Top that with great performances from Caradine, Daryl Hannah, and Lucy Lui, you really have an epic sequal(or volume)better than the original. Top that off with Taratino's amazing directing and the kick ass fight scenes, I choose to vote for Kill Bill Vol.2.