Good piano pieces for a wedding?

[qiyue]

I'm looking for highly emotive, "happy" or delicate sounding pieces for a wedding.
I claim complete ignorance on the subject although I am able to appreciate good music, I just don't know where to start looking. If people can point me in the direction of the best performers or your favourite pieces that you think would suit a wedding, nothing too heavy or sullen, they are young, happy and very much in love.
Thanks so much for taking the time to help me out.

[markymark]

Consider some of these:

Air from Suite No. 3, J.S. Bach

Canon in D, J. Pachelbel

Ave Maria, either the J.S. Bach or F. Schubert version

The Swan, Camille Saint Saëns

[Gill the Piano]

Look at some of the compilation wedding music CDs; then see if any of those pieces are arranged for the piano. Kevin Mayhew publishers often do very useful books along the lines of 'Wedding Music For Piano'.