As much as I hate the song, Hinder's lips of an angel is very easy to play and is, dare i say "uber" popular with the kiddies. If I were there, I'd punch you for playing it though.

Staying with that horrible band, Get Stoned is a faster rock song that's easy to play and rocks kinda hard.

Otherwise, how about AIC's Rooster for a slower, but still rockin song. It's also easy to play.