Anchors Aweigh (1945)
Kind of astonishingly good, and in a pleasantly surreal way, as Gene Kelly and Frank Sinatra con their way into Frank's courtship of lovely Aunt Susie, who's looking after the boy they randomly stumble across on shore leave. Real old school Hollywood charm.
White Christmas (1954)
Here's a Bing Crosby classic I've seen previously, but really only appreciated for the first time the most recent time I saw it. It's not just an excuse to hear the title song again (previously debuted in Holiday Inn), but rather to celebrate the soldiers who experienced WWII on the war front and who are still struggling to get back to what they "used to know."
Everyone (except Oscar voters) knows how brilliant an acting talent the late Peter O'Toole was, a magnetic and commanding presence completely unparalleled and never duplicated in film. Here he's Henry II to Richard Burton's title character, who at first is as close a match to O'Toole as anyone could hope to be, but soon enough undergoes a religious conversion that puts Henry and Becket at odds.
These are three movies that quickly shot themselves into the ranks of my all-time favorites. I don't tend to just assume that an older movie has earned immortality, the way some critics do. They have to earn their acclaim through their work. These do.