I Love Your Smile by Shanice has got to be a great wedding song. It is a classic that should get everyone on to the dance floor and has a romantic relevance to your day. Save it for about 45 minutes after the evening buffet has come out.
I Gotta Feeling by The Black Eyed Peas is a great upbeat floor filler that is full of meaning to both the wedding couple and the guests. It makes a wonderful second song, since the night has not fully started yet and lets be honest, you hope it will be a good night!