The American Adventure is one of the most innovative, artistic, inspiring, emotional, and AMAZING pieces of art I have EVER seen.
Journey into Imagination (original), Horizons, World of Motion, and Kitchen Kabaret were educational, good-humored, and at many points classic attractions, rich with song, character, a take-home point, and good storytelling.
Country Bear Jamboree is an entertaining show with classic Disney characters and gags that only Marc Davis and his team could think up.
The Enchanted Tiki Room (original) is a good slice of Walt Disney and Wally Boag. Walt Disney's Carousel of Progress holds the key to all dreaming and doing, a tribute to the past, present, and future in the context of simple family life. It translates Walt Disney's spirit to all generations.
Ellen's Energy Adventure is a hilarious film with a good balance between entertainment in education, an excellent example of a modern Epcot model. The score makes the experience priceless.
Dreamflight was just cool.
Those are my favorites.