Thanks Lurkina.n.Learnin ((((Hugs))))
When Pandro Berman, producer of the Astaire-Rogers musicals at RKO, hired the Gershwin brothers to do a musical, he told George to worry about the songs while he assigned the incidental music to Steiner and Bennett. Gershwin bridled at this, saying that if his name was going to appear on the credits, he wanted every note in the movie to be from his pen. Gershwin's offer to do the incidental material for free was music to producer Berman's ears. This was how "Walking the Dog" was written.
Lot of good ones mentioned above. Here are a couple I like.
IMHO the best rendition of the Marine Corp Hymn is from the movie Halls of Montezuma with Richard Widmark.
I also like the theme song from She Wore A Yellow Ribbon especially when they are leaving the fort. Here is a link to the song. http://www.youtube.com/watch?v=4BQPwob6-fI