My parents didn't allow Christmas decorations or Christmas music in our house until Christmas Eve. We would go to the Christmas Eve Family Service at 7PM, then come home and decorate the house with Christmas music playing. I had lots of brothers & sisters, and we used to get in a line, and my father would hand out ornaments one at a time, to go on the tree. Then we'd all hop back in the car for the 11PM service. Christmas Eve was really special for us.
My favorite memory was taking my young daughter for a walk on Christmas eve. It was lightly snowing and all the neighborhood lights were lit!
My favorite childhood memory is of a "special" night when our whole family was putting up Christmas lights on our house. It seems like several neighbors were out at the same time and everyone was decorating at once. It felt like the scene to a movie.