Can you give a date for your house? The Georgian period lasted a long time.

Anything by the Wesleys would probably be suitable and a number of the traditional carols like "God Rest Ye Merry" and the original version of "Deck The Halls" (not the sanitised version people sing now).

Most of the medieval carols were given new tunes in the 20th Century by people like Elizabeth Poston, but some (like "Down In Yon Forest") were still being sung when Vaughan Williams collected them (no guarantee the tune was original, but you'd be surprised).

:-)
Ian