By Christian Cintron, Hollywood Staff
Performing is performing. 'Nuff said. But there are different skills for singing and acting. You wouldn't want a dance track by Patrick Stewart featuring Ian McKellan (okay, bad example, that sounds awesome). You also wouldn't watch The English Patient with Justin Bieber. Or Apollo 13 with the boys from 98 Degrees. Or Crossroads with Britney Spears. But music artists like Mark Wahlberg, Queen Latifah, and Mandy Moore have all found great success by answering the call of the silver screen. Acting and singing are two different skills but some singers have managed to give some really amazing performances. Here are a few of our favorites.