Oso is correct... the opening credits for Star Trek III have now been "windowboxed" on the Blu-ray presentation. The DVD never did that. A lot of the James Bond films on BD suffer the same credits treatment unfortunately (OHMSS for example).

I just want to note a film that is not altered for BD, but has the most mind blowing use of variable aspect ratios within a movie ever. That film is More American Graffiti. Has anyone ever seen this? It basically follows three different stories throughout the film. Each character's story is presented in a different aspect ratio. I realize it's not part of this list as it's represented correctly on BD, same as the theatrical presentation. I'm just pointing out that I've never seen another film that took this concept quite so far. Not a great sequel by any means, but the John Milner character arc is the best and it's presented in pristine scope.