When I was little, I used to think that when you were fired from a job, it meant that your employer was mad at you and put you in a burning furnace to "fire." The strange thing is that it never seemed to cross my mind that if someone was fired by my definition, they would be killed, and I didn't seem to be worried that my parents or anyone I knew would get "fired."
Back when Jim Carrey started to become an A-list star in 1994 and I started to learn about his pre-Ace Ventura roles, I had a number of odd things in my head regarding what I thought occurred in his earlier roles.
I first misread the title "Peggy Sue Got Married" as "Peggy Got Married", and wondered if that was the same Peggy who appeared in "The Mask". But that's not the weird part... For no reason I also had an image in my head that the movie was about Peggy Sue marrying a guy who resembled the Cryptkeeper from Tales from the Crypt, that the video cover was her and the "Cryptkeeper" in wedding attire inside a heard-shaped boarder, and that Jim Carrey played the husband (when I first read about Jim Carrey's earlier movies I thought he was the lead or co-star in all of them).
Regarding Once Bitten I assumed the movie had a theme song called "Once Bitten", before actually knowing for sure that there was a song with that title in the movie. But the tune in my head sounded more like a mix of the "Welcome Back, Kotter" theme and "Short People".
Also for no reason at all, I thought that "Doing Time on Maple Drive" involved Jim Carrey playing a delivery man (I guess I was thinking too much about the beginning of "Ace Ventura: Pet Detective"), and thought that the video cover, if it ever was released on video (I wonder why it's never gotten an official release, considering it had great reviews from critics), depicted Jim Carrey hanging from a clock tower, his hands grabbing on to the lower hand of the clock. Actually I think this was the cover of a Goosebumps (or Give Yourself Goosebumps) book and I just thought that would be the cover. I didn't know what "doing time" meant and thought that movie involved time somehow.
One of my first sources for info on Jim Carrey's pre-1994 roles was a book one of my friends had on Jim Carrey, which included a section on his movies. I didn't really read the book, just glanced through that section, but saw one movie listed as "Pink Cadilac", then forgot the title except for the "pink" part. Then I got a video guide book, saw "Pink Flamingos" listed among the movies, and assumed that was "Pink Cadilac".
While Jim Carrey was not in this movie, when I first saw the music video for "UHF" and saw Stanley Spadowski I thought he looke similar to how Jim Carrey looked in "Dumb and Dumber" and thought he played that role (and it does seem like the kind of role Jim Carrey would have played). On a similar note, I was reading the description and cast of "UHF" outloud to one of my friends (before either of us had seen it) and pronounced cast member David Bowe as David Bowie, he pointed out that David Bowie was the Goblin King from Labyrinth. I eventually looked in the index of actors and noticed the spelling difference between David Bowe and David Bowie, but before that, I noticed one of the musician parodies in the music video looked like how David Bowie looked in Labyrinth and thought that was David Bowie (I would later learn that Bowie's hair is not normally long - did he grow it out for Labyrinth or was he wearing a wig?). Eventually I wondered if that video guide mispelled Bowie for that entry and listed him seperately in the index, but then I noticed the name in the credits for "Heavyweights", thought he was one of the kids, and thought he'd be a kid character in UHF (in particular I thought he'd be the kid who drank from the firehose). Then I thought he was the midget in that movie, under the belief that a midget could believably play a kid.
Speaking of David Bowie, when I first saw Labyrinth I noticed his visual and vocal similarities to Walker from Teenage Mutant Ninja Turtles III and thought they were the same actor.