I’ve always been intrigued by Walt Disney‘s Lady and the Tramp (’55) because it’s the only animated feature to be shot and projected at 2.55:1 — i.e., the early to mid ’50s Fox Scope aspect ratio that was phased out in favor of 2.39:1 in ’56 or thereabouts. To the best of my knowledge all other widescreen animated features have been presented in either 2.39 or, in the case of Disney’s Sleeping Beauty, Super Technirama (2.25:1).
There’s a new extra-laden Disney Bluray coming out on 2.27, but you can order a region-free British Bluray right now for less than $20.

The newbie has a ton of extras [see below], but not the one I’d like to see — a 1.37:1 version that was created for theatres that still hadn’t installed CinemaScope screens by mid ’55.
Eight years ago Fox Home Video released a Bluray of The Robe (’53), the first Hollywood feature shot in CinemaScope. The Bluray contained an alternate 1.37:1 version that was shot concurrently out of concern that the CinemaScope version might be a huge flop. As it turned out the 1.37 version never saw the light of day.
From Lady and the Tramp Wiki page:
“Originally, Lady and the Tramp was planned to be filmed in a regular full-frame aspect ratio [i.e., 1.37:1]. However, due to the growing interest of widescreen film among moviegoers, Disney decided to animate the film in CinemaScope making Lady and the Tramp the first animated feature filmed in the process.
“[But] problems arose as the premiere date got closer and [an awareness dawned] that not all theaters had the capability to show CinemaScope at the time. Upon learning this, Walt issued two versions of the film: one in widescreen, and another in the Academy ratio. This involved gathering the layout artists to restructure key scenes when characters were on the edges of the screen.”
