Songs to wed by

My dear friend Vikki is getting hitched next month and we've come to the song selection part of wedding planning.  We need songs for the following moments of brilliance:

Intorduction of the newlyweds
Parents dance (one sutible for all parents, not specfic to dad/daugter or mother/son)
Cake cutting

These are goofy folks that enjoy happy, joyous kinda music.  Good with old fashioned, quirky, and sentimental; just stay away from the cheesy stuff! 

So what'cha got?