I think I've found the perfect film for Blu-ray - the one it was absolutely made for. A brilliant film - not really a children's film in any sense as it features death, loneliness, oppression of a senior citizen and attacks by a pack of dogs. The overriding theme is loss. However, for adults who have an open mind, this is a genuinely uplifting experience.
There are two reasons why I say this the perfect film for Blu-ray. Firstly, it's the best and most detailed transfer I've ever seen, with an astonishing amount of detail and excellent contrast range. I don't have a full surround sound system, but the soundtrack seems to make full use of the frequency range (my Rel sub-bass speaker was certainly working). Secondly, the aspect ratio is 16:9 or as near to it as makes no difference. This means that the picture fills the whole screen. I'm certainly not one of those people who would stretch a picture to fill the screen, and I'm not averse to having black bars at the top and bottom of the screen, or the sides, if that's the way the material is meant to be seen. However, I do think it's a pity that most films - even ones that don't demand huge, panoramic vistas - are shot in 2.35 or 2.39 to 1. These just don't translate so well to TV (unless you have an enormous screen) as ones that have a more modest widescreen ratio such as 1.85 to 1.
Storywise, this is way ahead of the much-hyped Wall-E (I could never understand the idea of a cute, loveable robot, particularly as this didn't even look humanoid). Several scenes in Up stand out: the early montage of Carl and Ellie's life together; the takeoff and flight above the city; Carl's realisation at the end.
The film is far from perfect - there's a certain sterility to CGI animation that I've seen mentioned by various people; the "adventure" storyline is not as compelling as the framing story; and, for a film otherwise so technically adept, the sounds of the dogs' voices are strangely unclear and difficult to understand. For these reasons I wouldn't put it in my top 5 films ever, but it certainly goes into my top 20. If you enjoyed Monsters inc, Toy story or Wall-E and haven't seen this yet, what are you waiting for?