I loved the Delta Dreamflight..I have about 30 seconds of it on videotape from my 1989 visit, but I wish I'd taped the entire ride. I never did see it when it was TWA's If You Had Wings.
I addition to closing the Superstar TV and replacing it with Doug Live On Stage, the Disney/MGM Studios also did away with the Monster Sound Show with Martin Short and Chevy Chase.
The Backstage Tram Tour used to have it's entrance next to The Animation Tour building.
New York Street was originally not a guest area. You merely drove past it during the Tram Tour. They later expanded it into what is there today.
The sound stages housing the Backstage Pass and Who Wants to be a Millionaire were originally used as working sound stages, so there was a good chance you would see something being filmed as you went through the "Inside The Magic Special Effects and Production" Tour.
The tour was hosted by different Hollywood stars appearing on the monitors above. Mel Gibson, Pee-Wee Herman, Warren Beatty, Bette Midler...all discussing various facets of film production.
At the end they showed a short film starring Bette Midler that was partly filmed on the New York Street set and as you left, you walked past various indoor sets used for the film. These sets were later replaced by the 101 Dalmations sets and I believe currently hold sets from The Haunted Mansion.
The building that now holds Playhouse Disney was for many years the Soundstage Diner.
When it first opened it was themed around the Bette Midler/Lily Tomlin comedy "Big Business" with lots of props and sets on display. It later changed it's theme to Beauty And The Beast and then Aladdin's Oasis when it became a Character Buffet restaurant.
Journey Into Imagination had the 3D film Captain Eo for many years.
Spaceship Earth was originally narrated by Walter Cronkite.
The Land had The Kitchen Kabaret Revue starring Bonnie Appetit which later changed to Food Rocks (now gone to make way for Soarin' Over California).
The Universe Of Energy orignally didn't have Ellen and Bill Nye playing Jeopardy...and was all the better for it.
Long before Innoventions Epcot had the Communicore West and East.
Fantasyland had the 3D film Magic Journeys (which moved from Epcot when Captain EO arrived) and later replaced it with the puppet show The Legend Of The Lion King.
Mickey's Toontown was originally created as Mickey's Birthdayland (I believe it was 1987), then after the birthday celebration ended, it changed to Mickey's Starland.
Tomorrowland had Mission to Mars before the Extra Terror-estrial moved in.