Some great movies. Can't argue with "The Decks Ran Red". Besides the great Liberty Ship footage, there was some great Matson liner footage at the beginning and a decent explanation of why the Liberty was sailing under Matson colors. While the plot was screwy, the interplay between the crew and the new captain worked.
"The Sea Chase" as been a favorite, and "Action on the North Atlantic" is also a good, of corny, one.
Don't forget "Lord Jim".
Oh, and I have always had a soft spot for "Yellowbeard".