A stunning visual trip for the eyes, a can't-help-but-sing-along musical for the ears, and an all-around entertaining & plotless adventure for kids and the young-at-heart. Even it sags here or there (or gets a little too surreal), the fun songs, delightful animation, and wordplay make it a wonderful film.
It's hard for me to write a fairly critical review of "Yellow Submarine," as I've grown up watching it (I've probably seen it 25 times) since I was young, and I love it to death. The mismatched art styles, the completely arbitrary musical numbers, the irreverent asides and drug-addled loopy dialogue. It just never gets old, and is probably one of the most entertaining animated films of all time.
An absolutely perfect tonal switch from the popular animation of the time that brilliantly captures the generation, its music, its style, its values, its sense of humor etc. While the plot is barely more than enough to hang the various Beatles songs on there is so much originality that the characters rival the Beatles themselves in memory.