I haven't seen the Batman: The Dark Knight Returns Part I DVD as yet and I'm not sure I will spend the money on it (maybe I can put it on my Christmas wish list). When I read Batman: The Dark Knight as it was originally called, I was excited because it was being done by the same folks who had given me those great Daredevil issues--on the other hand, they had done Ronin, which I found less impressive. By this time I had been reading Batman for twenty years and I had read several stories that theorized about Batman's possible future--not to mention stories about the futures of Superman and other DC characters--so I took it all with a grain of salt. And a good thing, because I could never really believe this story as the definitive possible future for Batman. It seemed more like it was trying to be deliberately subversive of what one should expect at every turn. Right up to that final showdown with Superman. For all those years I had been reading about the great camaraderie between Batman and Superman and this book pretended to piss all over that. Pretended, because I never took any of it seriously. It seemed to be a joke--Miller was having fun pissing on everything and I enjoyed it on that level. I knew that it was totally false to the characters and it was therefore of no consequence. There was no big wow moment for me at the end.
That's very different from how I read All-Star Superman. While there were moments where I felt that Morrison was deliberately getting the characters wrong (in particular Jimmy Olsen and Steve Lombard), it felt true to the over all spirit of Superman. So when it comes to its big conclusion, that conclusion felt right and therefore much more epic because it drew on my sense of the character. It wasn't just turning everything upside down to get a rise out of me, the reader.
The DVD was much less effective in that regard, since it didn't take the time to build up the character of Superman and pull on all those associations.