Just as an example we had:
Right at the beginning was a piece from Phantom of the opera.
(The usual) Bryan Adams - Everything I do- for my entrance
Van Morrison - Have I told you lately
Nick Lachey - This I swear
Elvis Presley - Can't help falling in love
Bic Runga - Sway (American Pie soundtrack I believe all though I didn't know this at the time)
Quite a collection but it all worked really well, as the others say it's what means the most to you, perhaps you can think of a song that has a meaning to a poingant part of your life i.e. when you met your partner etc??