1. The Thin Man: Just the very best. This, as far as I know, is the seminal portrayal on film of spousal sleuthing banter, and no one did it better than William Powell and Myrna Loy (with an assist from Asta). Powell was reportedly every bit as charming and decent a chap in real life as he was as Nick Charles, which may be a reason he worked so often.
2. It Happened One Night: Arguably the seminal opposites-attract-on-a-road trip film. Midnight Run, you owe a debt of gratitude to Clark Gable and Claudette Colbert. By the way, both Powell and Gable were married to the lustrous and luminous Carole Lombard, who was taken too soon in 1942. Winner of five Academy Awards, including Best Picture.
3. March Of The Wooden Soldiers: Laurel and Hardy, for the child in all of us.

Haven’t seen, should see:

4. The Lost Patrol: World War I, things go badly for the Allies.

5. The Black Cat: Horror

6. The Man Who Knew Too Much: Early Hitchcock