The Muppets: A Celebration of 30 Years (1986)

For the first time in their careers, all the Muppets (except the ones that couldn't make it, like the Doozers, Gorgs and most of the Fraggles) have gathered together in one place to celebrate their thirtieth anniversary and honor the one who brought them together: Kermit the Frog (and by doing so, Jim Henson).