The Patchwork Girl seen in a preview of Walt's later-aborted Land of Oz-inspired musical, The Rainbow Road to Oz.
Goofy's attempted suicide from "The Goofy Success Story", especially the sultry voice calling him into the water that gets more and more angry when he resists.
The ending to "Disneyland Showtime", where after the Osmond brothers exit The Haunted Mansion, they realize that Donny is not with them. As they start calling for him, it pans up to see ghosts flying above the mansion as scary music plays.
Donald's "Nightmare sequence" in Down and out with Donald Duck. The whole thing.
Older Than They Think: Decades before surround sound home theaters became common, Walt Disney had some cities telecast "The Peter Tchaikovsky Story" in stereophonic audio by playing additional audio tracks over the radio. Because this could not be arranged in all markets, two versions of the episode were created. Both versions are included on the Blu-ray release of Sleeping Beauty.
Retroactive Recognition: The Osmond Brothers made their TV debut as a child barbershop quartet in the 1962 episode "Disneyland After Dark". The later appeared in the 1970 episode "Disneyland Showtime".
Seinfeld Is Unfunny: Walt Disney's Wonderful World of Color came during a time when color television was still a novelty and the show was responsible for a huge increase of sale in color TV sets. Heck, 50% of the nation didn't own a color TV until 1972.