For most of the last ten years, I have directed a caroling group from our Catholic parish here in Northern California. We hit 8-12 nursing homes, and sing a mix of secular and traditional religious carols. I tell stories about the songs in between, sometimes mixing in stories about family traditions or Christmas movies (e.g., White Christmas and Holiday Inn, Christmas on 34th Street, It's a Wonderful Life, Christmas Carol, Polar Express, Charlie Brown Christmas) and favorite performers like Bing Crosby, Gene Autry, Julie Andrews, and Mel Torme.
Here's our usual song list:

Deck the halls
Away in a Manger
I'll Be Home for Christmas (though some of our singers think this too sad for nursing homes)
Jingle Bells
Frosty the Snowman
Rudolph the Red Nosed Reindeer
The Christmas Song (Chestnuts Roasting)
God Rest Ye Merry, Gentlemen
O Come All Ye Faithful / Adeste Fideles
Hark, the Herald Angels Sing (tied with Hark, Hark, the dogs to bark)
Angels We Have Heard on High
Joy to the World
Up on the Housetop
I'm Dreaming of a White Christmas
Silver Bells
Little Drummer Boy
Silent Night
We Wish Me a Merry Christmas
Feliz Navidad

If there's time like to add "Winter Wonderland" and "Let It Snow."

If it might be helpful, I can email you a lyrics sheet and background notes. Just let me know at joe@mudcat.org

-Joe-