When listening to daughter's tapes (which have lots of good songs - she's got good musical taste), occasionally an unusually gorgeous voice comes on. I don't always love the songs, but the voice is wonderful. It's always Christine Aguilera.
Here's the video with wonderful singing, swing dancing, costumes, and general fun (also some off-color lyrics, so be warned):
And, if you want to show your kids this video, without the innuendo, click here for the "squeaky clean version."