I read the LITTLE NEMO: ADVENTURES IN SLUMBERLAND submission and have another Ray Bradbury kindertrauma: THE HALLOWEEN TREE (1993)!
I didn't find this movie in your archives, although if I missed it and it is, I apologize. I don't remember all that much about the movie (I only watched it once and was terrified) but the thing that I remember (which helped me Google and then Wikipedia it) was that there was a sick boy with freckles (Pip) who had a doppelganger pumpkin. I hated that pumpkin face. In the movie, Pip had to be rushed to the hospital on Halloween, but he appeared to his friends as a sort of ghost and they, thinking he was playing a prank on them, chased this apparition through some woods throughout the movie, and at some point, Ghost Pip acquired a pumpkin with his face.
After reading the description on Wikipedia, it's supposed to be a really nice film about the origins of Halloween. Too bad I could only think of SLEEPY HOLLOW and the pumpkin head and relate this film to that scary story.