the younger kids will love harpo and the tweens will love groucho being a smart alec. plus, it's only an hour long, so that helps them get over the whole black-and-white of it all ...
My son (9) and I just watched 4 Marx Bros movies on TCM. He is now a confirmed fan. He enjoyed the comedy and was amazed at the musical skills of Harpo (harp) and Zeppo /(piano). Also thinks Groucho is 'cheeky'.
Lovely old fashioned family fun.