"Material Girl," by Madonna
"It's cute and upbeat. Plus, nobody wants to hear a singer actually sing; it's more fun to just belt out a song."
The Grammy winner opens up about what life is like in the spotlight.
The singer on how she'd most like to spend a day off, her favorite travel spots and what's playing on her iPod.
The singer loves quiet time, a good pair of jeans, and chips and queso, Texas-style.
Find out more about Oprah's Karaoke Challenge, her nationwide search for the best karaoke singers! How to vote for a semifinalist.