Personally, I'm not that big on Christmas, never have been (even as a kid). But other people around me do enjoy it so I try not to be too much of a killjoy. I was the one that around the age of 5 or 6 informed several friends that there was no Santa Claus. What a right little *obscene gerund* *expletive-deleted* I was :-).
However, when I was really young (up to about age 10 or so), presents were opened Christmas morning. Then we started doing one present each Christmas eve. Later on (after my grandfather died and my grandmother started coming to visit for Christmas), my mom and I would take my grandmother to a Christmas eve service and then look at lights. When we got home, we would open presents. More recently, things have been a bit screwier since my grandmother died a few years ago. I've been working on the tradition of: one year we visit my fiance's family for Christmas, one year my family and then one year just us (no traveling, no family).