It makes me feel old that you all consider movies that I've seen in the theater to be "old" and "classics." Here are some true " classics" that I've loved:
Gojira -the movie from 1954 that started the kaiju craze. The acting is decent, the effects are landmark for the times and the social message is pointed. Even the version edited for US screens as Godzilla (including the god-awful Raymond Burr sequences) is good stuff.
To Be or Not To Be -I'm referring to the 1942 classic with Jack Benny, although the 1983 remake with Mel Brooks is also good. Jack Benny was a genius of comic timing and it shines in this movie.
Dracula -The original 1931 feature from Hammer Films is the peak of gothic film-making. Every other Dracula film after pales in comparison to the original.
Seven Samurai -From 1954. Akira Kurosawa film. Enough said. The US remake The Magnificent Seven (1960) also owns.
Road to Morocco -Bob Hope and Bing Crosby did some fabulous buddy pictures in the 40's with the Road to... series. This one is my favorite and it's damn funny.
Rope -From 1948, it's my favorite of Hitchcock's films.
Rebel Without a Cause -the classic James Dean movie from 1955. MoonUnit knows what I'm talking about.
Stalag 17 -one of the seminal movies about the WWII experience. Made in 1953, Stalag 17 featured a fantastic perfomance by William Holden.