Typically in the days before, I binge on Christmas movies, including some that not everyone else indulges in (Die Hard, The Disappearance of Haruhi Suzumiya, Tokyo Godfathers, Gremlins). Usually by myself.
On Christmas Eve, everyone in the family goes up to either my grandma's house or my aunt's house, and we schmooze all night and exchange a few gifts before heading back home.
On the day itself, everyone exchanges their gifts and then we watch a bunch of Christmas movies together (typically A Christmas Story, Home Alone, and How the Grinch Stole Christmas (1966)).
And that's that. Fun times, fun times.