Today, the selection is pretty much Big Music Star Free, other than Jewel as Dorothy, though at the time she was an unknown. There's also however a bit of Natalie Cole as Glinda the Good Witch, who's introduced with a nice touch of stagecraft, as well as a brief appearance by Debra Winger as the Wicked Witch. But mainly, in this segment we're introduced to Munchkinland, and the residents there are played by the Boys Choir of Harlem.
By the way, there's an interesting and very small moment around the 1:12 mark, which impressed me given how new Jewel was to all this, and wasn't a trained stage actress. But when the little boy playing Toto forgets to move, notice how she has the presence of mind to take his arm and politely direct him along. I also get a kick out of how she gets carried away with the audience clapping along with "Ding, Dong, the Witch is Dead" and joins along with them. (As you can tell, I like "little moments." I find in their attention to detail they reveal a lot.)