The 2nd movement of Nancy Galbraith's Piano Concerto (she's only written one so far) would be perfect, but a recording of it is hard to find.
2nd Movement of Bartok 2nd Piano Concerto
2nd Movement of Rachmaninov 3rd Piano Concerto
Lots of Brahms piano works (perhaps some intermezzi?)
Chopin Nocturnes, specifically B-flat Minor and E Minor
Schubert Impromptu in G Flat (op. 90 no. 3)
Some orchestral stuff/wind stuff:
David Gillingham-Be Though My Vision (written in memory of the composer's parents)
Frank Ticheli-An American Elegy (commisioned by Columbine High School)
Prokofiev-All sorts of stuff. Check out the Romeo and Juliet Ballet, for one.
Some of the Mozart operas are quite depressing as well.
J.S. Bach- some of the movements from the Mass in B Minor and St. Matthew Passion can get the water works going.