J. S. Bach, Jesu, Joy of Man's Desiring, duo

This movement works well as a part of the prelude or the procession.

J. B. Breval, Duo in G major

This light French duet is very suitable for the reception, dinner, or cocktail hour.

W. A. Mozart, Serenade in D major, trio

Another excellent piece for the reception.

A. Corelli, Sonata IX, Opus 5, Preludio, duo

Corelli Sonatas set the mood very nicely in the prelude.

A. Corelli, Sonata IX, Opus 5, Giga, duo

Another movement from the same Sonata.

G. F. Händel, La Rejouissance, trio

This is a favorite recessional piece.

Pachelbel, Canon in D Major, quartet

One of the most popular pieces for the entrance of the Bride. 

J. S. Bach, Air from the Suite in D major, trio

This is an excellent prelude selection, but can also work as the processional.