Annie Hall (1977)
Though it still has many off-the-wall comedic moments (breaking the fourth wall, slapstick) this film was a departure from Director Woody Allen's previous work in farce and satire, and it opened the door to his later work in more "serious" comedy and drama. Of course, as Roger Ebert observed: Annie Hall is probably everyone's favorite Woody Allen movie. (I think mine is actually Hannah and Her Sisters. . . or Bullets over Broadway . . . or Manhattan . . . or maybe it is this one.)
Snow White and the Seven Dwarfs (1937)
This film was the first full-length cel animated feature, and Walt Disney had to mortgage his house in order to finance the nearly $1.5 million production costs. Now, as you have probably figured out, Walt managed to cover his mortgage off of the success of this film and then some, effectively launching what would become the Disney empire. Obviously, this film has historical significance, but is it actually better than the many Disney films that would follow: Sleeping Beauty, Beauty and the Beast, The Lion King? Hard to say. I suppose that there are a few films on this list that are "weighted" in the same way. I'm not going to be the one that says Sleepy, Dopey, Sneezy and the gang shouldn't be here.
One Flew Over the Cuckoo's Nest (1975)
Jack Nicholson as Randle P. McMurphy, a small-time criminal gaming the justice system to serve his sentence in a mental institution instead of in a labor camp, is an anti-hero with the emphasis on "anti." That his anarchist sensibilities have him leading a revolt against the unyielding authority of Nurse Ratched likely surprises McMurphy as much as anyone. The performance earned Jack Nicholson his first Oscar, and the movie itself took "the Big 5" for that year (Picture, Actor, Actress, Director, Screenplay.) Brilliant movie.
The Godfather Part II (1974)
This film takes the unique approach of simultaneously being both a sequel and a prequel to the hugely successful first Godfather film. We continue the story of Michael Corleone (Al Pacino) having stepped into the shoes of his father, Vito Corleone (Marlon Brando in the original) as the head of the Mafia family while we also look at the rise to power of the younger Vito (now played by Robert DeNiro.) In my opinion, this film is such a good sequel that it is inexplicable to me that it would fall anywhere else on this list other than immediately following its predecessor (#2 on this list). In fact, there is a version of the films edited together in chronological sequence (with some added unused footage) called The Godfather Saga. I haven't seen it myself, but - when I find myself with seven hours to kill - I think it would be an intriguing way to see the films.
The Maltese Falcon (1941)
I love detective stories. I particularly love good ones, and this hard-boiled story by Dashiell Hammett is one of the best. Brought to the screen by John Huston as a slick noir thriller, this adventure of Detective Sam Spade (Humphrey Bogart) set the standard for gritty crime dramas for years to come. If you haven't seen this film, I highly recommend it, and -for added fun - I would suggest viewing this as a double feature with the 1946 film The Big Sleep (Bogie as Raymond Chandler's Philip Marlowe). Let me know when you do. I'll bring the popcorn.
The Big Sleep didn't make the AFI 100 list, and that's a shame, because it is another of my favorites. It's been remade a couple of times very well, but the 1946 version with Bogart and Bacall is the best.