Film: Die Hard. If you must have a Christmas film (and you must), make it this one. It really brings out the spirit of Christmas; "Ho Ho Ho, now I have a machine gun". Alternative: White Christmas. It's a bunch of Irving Berlin numbers stitched together by a fairly slight plot! Also they should actually be in drag in this scene. If you can get past that, it's amusing, light and not too demanding, which is what you want to watch at Christmas. For another view of the film, there's Brokeback Christmas.
Song: Santa Claus Is Coming To Town, Bjorn Again. It's like all our ABBA Christmas fantasies coming true! Assuming you have ABBA Christmas fantasies. Alternative: Little Drummer Boy/Peace on Earth, Bing Crosby and David Bowie. The conversation at the start is kind of amusing; the whole pretending they don't know each other shows that Bowie is not a comedian, but Crosby is.
Food: Roast Goose. How do you roast a goose? Dad has boned ours. It should cook quicker and will be a doddle to carve. Do we lose flavour? If so, it's gone into the stock as he's cooked the bones up with the giblets and trimmings, reducing our large stockpot full down to... well down to two jugs that are filling up a large amount of the fridge, and a saucepan that won't go in. Anyway, if you don't do that, don't forget to prick it and turn it over to brown the back and let all the fat drain off. Use the fat for roast potatoes (or not; Heston Blumenthal says that this is fine as long as you want your potatoes to taste of goose. He prefers to use olive oil; also he notes that you can flavour the oil with your potato peelings as most of the flavour of the potato is just under the skin. Blumenthal is clearly both a madman and a genius; potato flavoured oil for roasting potatoes in! Alternative: Pickled Onions. It's too late to pickle your own for Christmas, but the important thing to remember is to soak them in brine twice for 24 hours before cooking up the vinegar and spices; introduce the onions to the vinegar when you take the vinegar off the heat.
Book: A Christmas Carol, Charles Dickens. It's always A Christmas Carol. Alternative: Don't Cry for me Aberystwyth, Malcolm Pryce. Father Christmas is murdered in Aberystwyth; as we know he comes from Greenland, a self-governing overseas administrative division of Denmark, so the Queen of Denmark hires Louie Knight, Aberystwyth's celebrated private eye, to investigate. It's comedy, although dark and tragic too. Makes more sense if you've read the previous Louie Knight thrillers.
Wild Card: Talking of Trebuchets (as we were) here's the homepage of the Warwick Castle Trebuchet. Alternative: a youtube video of what claims to be a world record trampoline jump. Bonkers.