Your small group party doesn't have to be elaborate, it just has to happen. Have it on your regular group meeting night. Make it a potluck party where everyone brings food. Have a "red" and "green" potluck, where every food has to be red or green, even if it requires food coloring. Nothing like lime jello and cranberries!

Put someone in charge of finding words for Christmas carols and printing enough for everyone.

Take the whole group out into the neighborhood the night of the party for Christmas caroling - just 4-5 homes will get everyone in the spirit. Don't let the naysayers keep the group from doing this. Be a little forceful, lead people out, everyone will have fun and thank you later.

Have someone read the Christmas story from Luke 2:1-20.

Maybe one member of your group is a storyteller. Have them make up a Christmas story and tell it at the Christmas party.

Have a "white elephant" gift exchange.  Play some Christmas games like Secret Santa. Spend just a few minutes on the Internet and you'll find hundreds of games for Christmas parties.