Silly Symphony - The Skeleton Dance (1929)

The Skeleton Dance is a 1929 Silly Symphonies animated short subject produced and directed by Walt Disney and animated by Ub Iwerks. In the film, four human skeletons dance and make music around a spooky graveyard - a modern film example of medieval European "danse macabre" imagery. It is the first entry in the Silly Symphonies series. In 1994, it was voted #18 of the 50 Greatest Cartoons of all time by members of the animation field.

source: http://en.wikipedia.org/wiki/The_Skeleton_Dance