The end, when Holden realizes that he can't hold onto the freedom of childhood forever, and that he has to let Phoebe grow up, regardless of the inevitable onset of 'Phoniness'. Doubles as a Crowning Moment of Awesome.
When Holden goes back to his apartment and dances with Phoebe while their parents aren't home.
Holden may be of questionable morality, but he truly loved some people.
His deceased brother's death got to him so much that he punched every single window in the garage. The narration describing their interactions helps.
Look above. Phoebe, his smart-for-her-age kid sister.
Jane, his childhood friend. Their interactions in the past are adorable, especially when Holden comforts her about her alcoholic father. Shame they don't get together, but she's still in town...