Just because its Christmas does not mean that you HAVE to have turkey.
If you are worried about waste, most Thanksgivings I get a small turkey breast to roast as it's just DH, DD and I for a midweek dinner - we might get 1 turkey sandwich from the leftovers.
In fact, I just did it again last night, only it included neighbours this year, so a larger breast for "8-10 people" (M&S freezer section the day before) - I fed 7 and there's enough for a small 2 person dinner leftover. 3 packs of parmentier potatoes from M&S, 2 tins of sweetcorn and some other veg from freezer (that I had pre-prepared, not with TG in mind), and a dish of HM stuffing (admittedly, that took about 6 minutes of prep and 25 minutes to cook - due to 20 minutes slow gentle frying of onions that I could mostly ignore while I tidied after Wednesday's dinner, on Wednesday night). It was on the table 2 hours after I turned on the oven, with minimal prep. (Which included me going back out to collect DD from school, corralling her to change into her Scouts uniform for her meeting, and setting the table etc as well).
It's nice to be able to spend time, as the day is a much slower pace, making a meal that you enjoy preparing and enjoy eating. THat doesn't need to mean hours in the kitchen, we tend to do 20-30 minutes getting it going together, and then someone pops in to baste things, or put another tray into the oven, at different points while we are opening presents and enjoying a glass of wine in the sitting room.
It's not about fussing over 20 different sides and 5 sauces just because it's Christmas.
Our starter is a tray (or maybe 2 if we fell particularly hungry) of M&S party food which is put into the oven while we get things organized, and then eat while opening presents.
Cheese board comes out about an hour after we finish main course.
And dessert is usually another hour after that - we like to let the meal settle and not rush it.
And if the DCs won't eat turkey, why inflict it on them?
If you and DH really want it, get a small piece to give you dinner and enough leftovers for sandwiches for 1 day (so DC can taste it if they are interested, as much as wanting sandwiches).
But what would the DC really like, that is not TOO much hassle to make? Would they eat a different meat - sausages, fish fingers, chicken goujons? - with potatoes and veg? Or will they be looking for something like pasta, or pizza?
And what would they like for dessert? Jelly and ice cream? Some little brownies or doughnuts? Fruit salad?
Would they eat crackers and grapes off a cheeseboard, if you and DH actually wanted cheese? Or have a mild cheese that they might like, even if you wouldn't normally put it on a cheese board - what is Christmas without a couple of cheesestrings?! (As in, that means they feel they are part of it).
Make it a special dinner in a way that is meaningful to YOU. Would you and DH like a fillet steak, because you never get to treat yourselves to that? 2 pieces of fillet would be a lot less than a whole turkey, I'm guessing.
Or do you want to cook something that takes hours of long slow cooking that you can mostly ignore like a small leg or a shoulder of lamb or of pork.
A really good stew or tagine.
A particular dessert that you can enjoy later on when the DCs have gone to bed.
And you can have it either in the middle of the day, or in the evening around normal dinner time - or you can even be totally rebellious and have it mid afternoon when a good hearty breakfast has worn off, but not so late the DCs will still be over-full when it gets to bedtime.
On a separate note, in terms of having some nice things for you and DH to enjoy and perhaps tempting DCs to trying new things, we started doing "platter" dinners a few years ago. It started as a Christmas Eve thing, and we now do it maybe once a month or so on Sundays as DD really doesn't like roasts. Nice sliced cooked or cured meats (nice regular ham, parma ham, salami, etc), cooked prawns (all shell off), smoked salmon, olives, carrot and pepper sticks (for dipping), hummus, pesto, breadsticks, cherry tomatoes, a couple of cheeses, crackers, ......not all of these together, but a mix of a few different bits and pieces to enjoy, with Christmas Eve versions being a bit more luxurious.
The interesting thing was that when everything is put on the table in the middle, for people to serve themselves, they will eat more. You need to make sure there is sufficient that you KNOW the DCs will eat, but put a few things that you like that they are not keen on or haven't tried before - when they are not being forced to by it already being on their plates, but just by watching other people choosing and eating it, they are more open to trying a little bit, and having some more if they like it.
Just because Everyone Else does it one way (and the reality is that - no they don't all do it that way!), doesn't mean that you shouldn't adapt Christmas Day to make it exactly how YOU and DH (and the DCs to an extent - but knowing you and DH will be doing the work) want it to be.