Greetings in that Divine and Most Precious Name of Our Lord and Savior Jesus Christ!
This will be the first Christmas we celebrate on our journey to Orthodoxy. I have a few questions...
On past Christmases, we would sometimes go to Mass on Christmas Eve, followed by a big get-together for the whole extended family at someone's house (not only is it Christmas Eve, but my grandmother's birthday!), and then Christmas morning was for presents and relaxing, and getting ready for dinner. Do Orthodox go to church on Christmas Eve or Christmas Day? Or both? We will be spending Christmas with my parents (12 hours away), and I already know that it will be a battle to go to church at all, let alone Christmas morning. If you do the Santa thing, do you go to church first, and then open presents? How do you get your children to walk by all the presents w/o opening them? Our son is 3 1/2, so I would like to start a tradition now, when he is young. Any advice would be greatly appreciated.
Congratulations!
You should ask your priest and folks at your parish what their traditions are, each locality tends to celebrate a bit individualistically. The Midnight Christmas Eve Liturgy service tends to be fairly universal, but how it plays it is whats different. In our Parish we have Liturgy from 5pm-1am, then choir and sermons until around 3-4am, then we have a huge festival breakfast of meat and tasty dishes in the spirit of joy and fellowship. Folks tend to get home around dawn or later, and so we here skip the Christmas Morning service, though many many parishes I understand have a Liturgy on Christmas morning as well. The Santa thing, the presents, those are really a family matter, I do not know if these are done in a public kind of way, I believe it is for the home.
Further, Orthodox Christmas is on January 7, so I would assume it would be safe that you would not have a conflict over family versus Liturgy, I would imagine you will get two Christmas celebrations this year. In my family who are Baptists, we do the American Christmas thing on December 24/25, and then I have the Orthodox celebrations appropriately on January 6/7. I would advice you to highly prioritize attending a Liturgy service on Orthodox Christmas, it should be a life changing experience, and you should aim in the Grace of God to put nothing before it. This is Orthodox, to participate in the Liturgy is central and above any and everything else. This is entirely where the American tradition of only attending services on Easter and Christmas evolved, from the absolute importance of these Liturgy services on the calendar.
My advice, ask around, after all its the Christmas spirit, people will be joyous to share it with you

stay blessed,
habte selassie