I guess the most recent was The Treasure of the Sierra Madre, 1948, which was just on tv within the last week or two. Before that, several of the holiday movies already mentioned above. On the Waterfront was on a few days ago, but that is from 1954 so ineligible!
Now you have me wondering what the earliest movie I really enjoy is. I know there were a lot from the early 1930’s, but what about before that?