We have the extended family over on Christmas Eve Day and open presents. That way the families with young children can get them home early at night. On Christmas Eve Day we open presents from the extended family and they open our gifts. We save our personal gifts for Christmas morning.
On Christmas morning (and Christmas Eve Day), we do eat breakfast and then we open presents. We have Christmas music playing, drink hot chocolate with marshmallows and take turns opening one gift at a time. We also have the candy canes hanging on the tree so that everyone can have what they want. We video tape the whole thing and just enjoy being with each other.