A classic question that for movie lovers is next to impossible to answer, especially without some category breakdown. So a partial list, in no particular order, would be:
Epics: Dr. Zhivago; Out of Africa; Dances with Wolves; Gone with the Wind; Godfather I&II
Musicals: Wizard of Oz; Sound of Music; Chicago; Funny Girl
Romance: Laura; The Ghost and Mrs. Muir; Sabrina (1954); A Walk on the Moon; Guess Who's Coming to Dinner; Shadowlands; Goodbye Mr. Chips
Drama: Casablanca; North by Northwest; American Beauty; All About Eve; Dead Poets Society
Foreign: Indochine; Raise the Red Lantern; Crouching Tiger, Hidden Dragon
For me, there's simply too many great movies to choose from, as evidenced by my lengthy list. And the list could be so much longer
Karin