Choosing what music to have at your wedding ceremony can be very difficult. It is ideal that you choose music that will go hand-in-hand with your theme and tone you are setting. For a traditional ceremony you usually have a song for the moms and dads to come out to, bridesmaids and groomsmen, the bride alone with her father, and one that the groom and bride leave to. If you're having a Catholic, Lutheran, or other religious ceremony there can be even more music and songs.
At the wedding reception you may want to hire a band or DJ if your budget allows for it. They should know what kinds of music to play at your wedding but you may want to give them a list of requests. If you're having your couple's first dance, father/bride & mother/groom dances you will want to give them not only the songs/artists, but also the order in which to play them.
I chose to spend my budget in other ways and therefore didn't have a band or DJ play at my wedding reception. Instead I had my iPod connected to a large stereo with a playlist of songs for background music. When it came time to for special events, my brother announced the program and songs from the cutting of the cake to the bouquet and guarder toss, as well as the couple's first dance and the father/bride & mother/groom dances. A playlist of songs on your iPod works out very well, and more and more brides are choosing to do this.
You should choose songs that will make your guests want to dance and celebrate with you. If you're having an actual dance you should have both fast songs and slow songs. Play songs from all decades so all generations will recognize and dance to.
Some people choose to split up the father/bride & mother/groom dance. I recommend not splitting it up and combining them. Start out with the father/bride dance and have the mother and the groom join in party way through. No one wants to sit and watch two of these kinds of dances that can last four to five minutes each. If possible, edit the couple's dance song and the father/bride & mother/groom songs to a minute or so each. Guests also don't want (nor have the attention span) to watch you dance for 10-15 minutes. Trust me, it gets awkward.
Lastly, I recommend practicing the dances to the music. You can't just get up there and wing it or everyone will know that's what you just did. Some brides are intense and have dance lessons like in the movie, The Wedding Planner. I don't think that's highly necessary, but you should practice a few times with your groom and your father. No one wants to watch you go round and round in a circle while you gaze into each other's eyes. Add some spins in there and finish with a striking pose. You are entertaining your guests during these dances so make it fun for your guests to watch. Plus, you don't want your dad getting up there and embarrassing you. If you don't practice with him he will!
If you're going to finish with a bang and have a dance party at the end, you should! That's what your guests came for. Have your bridal party help and get your guests up on the dance floor and movin' to the beat. My dance party was a hit and my grandma got up and started dancing her little tail off. The guests love it so I always recommend a dance party.