Are you looking for good songs to get people up and dancing? I was at a wedding just this past Saturday and the DJ did a good job getting a lot of people going, so here are some songs that are fresh in my mind (no particular order):
Cadillac Ranch
Locomotion
Billie Jean
Thriller
Time Warp
I knew the Bride when she used to Rock & Roll
I would walk 1000 miles
Cottoneye Joe
Sugar Sugar
Hmmm... that's all I can really recall right now. I guess it depends on the crowd but those songs in particular were pretty fun this past weekend.