...I'd best point out that my 7 year old urchins were so hot and limp with flu that they would have sat, watched and enjoyed 2 and a bit hours of film about, say, creosote.
So 'It's a Wonderful Life' was a breeze.
...this film doesn't make sense in a few ways. It is quite long, 130ish minutes, and you only see the angel, 'Clarence' for about the last 25 of those. The structure would seem to be all wrong. It ought to break it's own back in the middle and everyone should walk out bored.
In fact, to a degree this is what happened when it came out. It wasn't a big success, and only became one when the US tv networks started playing it to fill gaps in schedules...
...it is one of those films that improves with multiple watching. The wonky structure ceases to matter, and it doesn't matter either that you know what is going to happen...
It shouldn't work, but it does!
(er, like the Muppet Christmas Carol. Michael Caine and a bunch of post modern puppets? Shurely Shome Mishtake...)