We had one song and it was Songbird by Eva Cassidy.... I think if you had 2 songs it would break up the nice flow....
Just need to use live musicians for it, but easily done. I've been a musician in a wedding where we did a medley of about 3 pieces (can't remember names).
Who ever said they used gabriels oboe... It has to be played on an oboe ffs. It's ruined on anything else (although the lyrical version is nice.)