I walked down the aisle to a song that DH and I first realised we both liked when we were dating... the words held meaning to us, so we had it played acoustically for me to walk down the aisle to, and we danced to the real version as our 2nd bridal waltz song.
It was Everlong by Foo Fighters... we loved the verse "If everything could ever feel this real forever, if anything could ever be this good again... the only thing I'll ever ask of you, you've gotta promise not to stop when I say when"

Ohhhh... I am getting all emotional just thinking about it!!! lol
I am sure you and your DF will find the most perfect songs for your wedding too.