If you are talking about the DVD, then its probably the same one I got in 2003, which had alot of the same type of music in the 2002 version. My guess is that it is cheap generic music that is licensed for the DVD (much like the same screams you can hear a million times on these DVDs).
Now just becuase its cheap generic, doesnt mean its bad, I enjoy the music of the menus myself. I've heard at least one of the tracks on a infomercial once, thats where I got the idea of it being licensed.
The 2004/"Magical Gatherings" themed kit uses "Fantasy" as the menu background music. This track was found on the "Magic in the Streets" release from Walt Disney World during the 100 Years of Magic celebration.
A different version of the song is used currently in the "Share a Dream Come True Parade" at the Magic Kingdom park.