There are a few options. Ham and scalloped potatoes is a popular second place, for example - we've even done it some years.
But I think it's safe to say that the majority of families have what we call "Cooked Supper" (it's a specific thing, not just a general term), which is basically Jigg's Dinner but with a meat entree, usually turkey (including liver and neck). There are a couple of extra things I personally have not seen on the mainland, but you may eat it; I don't know.
So here's what we had today:
So starting on the left side with the potatoes and moving clockwise, it's: potatoes, pease pudding (my second favourite; it's kind of like our pea soup but with the consistency of mashed potatoes), carrots and turnip, salt beef (everyone's favourite, we fight over this), cabbage and vinegar, dressing, peas. In the middle is turkey and cranberry sauce. Mustard pickles, beats, and relish as sides.
This is the pease pudding cooking in its bag:
For dessert it could be absolutely anything, from anywhere - Timbits, Costco cake, macarons, whatever. We don't really have a dessert tradition so every family is different. In mine, it's always some kind of cake with berries my mother picks herself (partridgeberries this year), with either custard or sugary sauce made from scratch (we call it caramel, but it isn't). I take mine with coffee, but after-dinner tea is the norm, followed by a port or something Bailey's. My parents went super-Canadian this year and had some Bailey's knock-off with a maple leaf and maple flavour.
That main meal could be Christmas Eve or Christmas Day, depends on the family. Whichever day doesn't have that main meal, it's probably seafood for a plurality of homes (but certainly not a majority).
For example, last night (Christmas Eve) we had mussels, cod tongues fried with pork scrunchions (it's the filet mignon of fish, you will never taste anything more delicious from the sea - except sea urchin), and stuffed squid with dressing: