Klaus is a new classic for me.

Love Actually is the best Christmas romance by far.

Die Hard har har

Christmas Vacation because my whole family knows it by heart. Home Alone is the same for a large swathe of central Europe.

A Christmas Story

https://en.wikipedia.org/wiki/A_Christmas_Story

Die Hard

Tokyo Godfathers

https://en.wikipedia.org/wiki/Tokyo_Godfathers

Tři oříšky pro Popelku. There's no competition.

Not necessarily my favorite Christmas movie, but I always watch The House Without a Christmas Tree during the holidays:

https://en.wikipedia.org/wiki/The_House_Without_a_Christmas_...

Christmas Story and A Charlie Brown Christmas.