I only mentioned the John Wayne movie "True Grit" in a previous post in this thread. I'm not really sure that I can come up with a definitive list of favorite movies, there have been so many that I have enjoyed and have watched more then once.
BUT... having thought about it, the following list is a few that would populate any list of what I would consider "Classic" movie favorites.
To Kill A Mockingbird - Gregory Peck, Mary Badham, Philip Alford, John Megna
The African Queen - Humphrey Bogart, Katharine Hepburn, Robert Morley
Casablanca - Humphrey Bogart, Ingrid Bergman, Claude Rains, Paul Henreid
Dr. Strangelove - Peter Sellers, George C. Scott, Sterling Hayden, Slim Pickens
High Noon - Gary Cooper, Grace Kelly, Lloyd Bridges, Katy Jurado
Bridge On The River Kwai - Alec Guinness, William Holden, Sessue Hayakawa, Jack Hawkins
Ben Hur- Charlton Heston, Hugh Griffith, Stephen Boyd, Jack Hawkins, Martha Scott, Cathy O'Donnell
All About Eve - Bette Davis, Anne Baxter, George Sanders, Celeste Holm, Thelma Ritter, Gary Merrill
One Flew Over The Cuckoo's Nest - Jack Nicholson, Louise Fletcher, Brad Dourif, Will Sampson,
Lawrence Of Arabia - Peter O'Toole, Alec Guinness, Omar Sharif, Claude Rains, Jose Ferrer, Jack Hawkins
An American In Paris - Gene Kelly, Leslie Caron, Nina Foch, Georges Guetary, Oscar Levant
North By Northwest - Cary Grant, Eva Marie Saint, James Mason
There are more. The Lon Chaney, Boris Karloff horror movies. Some light-hearted comedies. Some of the SciFi movies.
I could go on and on and on... but I'll stop now.