This is an easy pick for me. The story for this film is pretty solid, and this film is well written. Also, Good Will Hunting is loaded with some outstanding performances.
Matt Damon was this cocky and rebellious genius, but he was afraid to take his gifts to the next level. Damon's character had all the tools to become a very successful man, but there were times where it seemed like he was in a shell. He didn't want to open up. Robin Williams and Ben Afleck had to push him to become a better man. Afleck's passionate speech towards the end of this film managed to open Damon's eyes, and he decided to pursue his love interest, Minnie Driver. Damon started to push Driver away, as she began to take the relationship to a serious level. Although, Damon turned himself around at the end of the film, because he realized how much he cared for Driver.
Also, the verbal duels between Damon and Williams were just great. They were full of intensity and emotion. During these therapy sessions, Williams was strong, and he refused to let Damon break him. There were times where Damon was a real dick, but still, Williams refused to back down. Williams actually managed to bring Damon to tears, and this scene is kind of shocking, because it brings that "Oh my god! He's actually getting through to him!" type of reaction out of you.
Good Will Hunting takes you on a journey. Damon's character can be a real jerk here, but I always want to see Damon succeed when I watch this film. I always find myself rooting for him, because his character does have that Average Joe feel, and this is the type of guy who you can root for.