Once upon a time, in 1988, when I was 2 years old and took my first trip to WDW, it was called Mickey's Birthdayland. I have on video the whole train ride there and the birthday show. I have heard that Birthdayland and the train station were all meant to be temporary but because it was a big hit, they kept it. The train used to be the only way to get to Birthdayland (We're rollin', we're rollin', we're on the express, Mickey's Birthdayland express! We've got a big surprise for Mickey, a birthday bash for Mickey, BIG surprise for Mickey Mouse!). It was themed to Duckburg and had a bunch of cute little storefronts and such.
Mickey's Starland had a show with the characters from the Disney Afternoon shows.