this is a really good movie based on this comic book series of the same name. it's an out of continuity book, so things can actually really happen and be effectively emotional in this.
anyway, I had no idea what it was about. I had read a blurb at some point, so after the first ten minutes or so when Superman rescued the solarnauts I remembered what it was about:
Lex Luthor give Superman a yellow sun radiation overdose, and it's killing him. it gives him a lot of extra powers. in the books he has a year to live, and in the movie it seems like it's less time. he does a lot of good stuff in both, even with Lois hanging about.
there's a lot of the Silver Age of Superman floating about in this one, kryptonite guns and gravity guns, Superman robots (sorta), the Phantom Zone, a baby Sun-Eater which is Clark's pet, Samson and Atlas (not that I knew exactly who they were in the movie) and even Lex's purple suit show up.
though if you clicked on the links you already know! I was wondering how they ended the movie, as no way would they actually let Superman, or Lex, for that matter die. well they sure did. he turns into pure energy and leaves to restart our sun, which Solaris has turned blue to feed off. the ending is really touching and is well done.
this is the best DC cartoon movie I've seen in some time. I recommend it.