Jacob Marley with Scrooge. Poor guy was so frustrated he dislocated his own jaw during one of his ghostly wailing fits.
The Ghost of Christmas Present may be a jolly figure, but do not bring up what the current bureaucracy of the Church of Christ is doing in Christ's name, like closing places once a week when the poor are so in need of help. He does not take such mentions well and considers them not of his church.
Creepy Child: Ignorance and Want. This adaptation makes them creepier than usual by adding a sequence where they morph into adults: a thug and an (implied) prostitute, respectively. They also get Present's line about prisons and wh--workhouses.
Did Not Do the Bloody Research: A guest at Fred's party is playing 20 Questions and guesses "Is it an arse?", meaning ass as in donkey. "Arse" will always be a rude word in Britain, and is certainly never invoked in polite Victorian parlour games.
Due to the Dead: The film begins with Jacob Marley's death and his corpse being prepared for burial with two pennies covering his eyes to keep them closed. Scrooge stole them from the body.
At one point, Marley yells so powerfully that he dislocates his jaw, then says the next line by moving his lower jaw with his hand (borders between disturbing and funny) before attempting to put it back and in the process folding his face up tightly to the point where he cannot speak (just plain funny).
One minute, Scrooge is being chased by demonic shadowy horses, the next he's crawling through a sewer pipe with a chipmunk voice. And then, back to the horses.
Never Trust a Trailer: The trailers made it look like a goofy, kiddy version of the story. The actual movie, however, was surprisingly faithful and kept most of the original's story intact, including the dark bits.
The five-minute title scene, starting with one conversation with Scrooge, flying all around London and then back down to the other side of the city, finishing with him approaching his house.
The entire "Ghost of Christmas Past" scene simply faded from time period to time period without any cuts.
In fact, Zemeckis seems an avid fans of The Oner, since nearly all shots in this film have multiple camera pans.
Playing Gertrude: Scrooge's nephew Fred is played by Colin Firth, who is actually older than Jim Carrey. The use of motion capture makes this less obvious than it might have been in a fully live-action movie.
A nod is also given to "Mickey's Christmas Carol" (another Disney incarnation of the tale) when Scrooge is hanging from a root in his own grave while a hellish light beams up from his coffin.
Sssssnake Talk: The Ghossssst of Chrisssstmasss Passsst - and not just the ssssibilants, but all the vowels. Considering how the Ghost was represented, its speech could be representative of the wisp of a candle flame...slowly guttering out.