Ive been doing alot of cover songs over the summer. Some that you may consider are Saosin- Time after Time. Brand New- Jesus Christ. Secondhand Serenade- Your Call. The Rocket Summer- Never Knew.
its been said but santeria is one of my favorite songs to hear played.
my friends have a tendency to play bluegrass versions of various hip hop/rap songs so if you can figure those out its always fun.
also, people like to hear the band - the weight and ocms - wagon wheel. fun sing a long type songs.