Do you and your fiancee have a selection of music that you've always considered "your song"? If it already has sentimental meaning to you, why not incorporate it into your first dance? This moment will be the first time you dance with your new spouse, so you want the moment to be special! Maybe the song isn't a traditional love song? Who cares!? As long as the overall theme isn't inappropriate and you would feel comfortable having your grandparents hear it, go for it.
If you prefer to go the more traditional route, and select something with the perfect tempo and beat, think about some recent artists whose music will be sweet and beautiful. Some of Michael Buble's best singles have become the go-to wedding song selection, but if you listen to the rest of the selections on his CDs, you will be pleasantly surprised to find additional songs that would be lovely, and less overplayed!
Maybe you consider your taste in music to be a little less mainstream, and a little more focused on the instrumentals. Artists like Dave Matthews Band and Ben Folds have a variety of songs that would make perfect first dance songs that your guests can enjoy with their easy listening vibes, but won't feel like they've heard it so many times before.
Do you consider yourself and your fiancee to be totally over the top and outrageous? Maybe you want to surprise your guests with a song that screams your personalities. In this case, if your going to go for it, go for it all the way! Pick an exciting and fun song like one of Lady Gaga's hits or even Ke$ha! This first dance is going to be totally different from anything your guests have seen before, so be prepared for some raised eyebrows, especially from the older more traditional friends and family.
No matter what your style may be, picking a song for your first dance is a part of the wedding planning process that the Bride and Groom should do together! Even if you have an old favorite you have been dreaming of using, maybe their is a cover of it by a more contemporary artist your fiancee would prefer to use. Take your time in making the perfect selection, and most importantly, have fun!