I'm a big fan of the Superman movies. I loved Christopher Reeve, he's the best actor that has played a superhero IMO. His Clark Kent is legendary.
I didn't like 'Superman Returns' much except for a couple of scenes (the initial credits were awesome too, like in the old movies!!). I still don't know why the scriptwriters wanted to give him a son though (I mean, was it necessary?!) But I think the 4th 'Superman' movie was the worst 1 too. It was just very poor. I also believe that the third movie has always been a bit underrated. Sure it wasn't as good as the first 2 movies, but it has an epic moment in the History of Superheroes: the bad Superman fighting against the good Clark Kent. That was simply brilliant.
I think the Spiderman scriptwriters took that idea for their third movie. The difference is, 'Spiderman 3' was a stupid movie for me. Great special effects, but a bad script with too many villains (Sandman was the best character in the movie) and Venom not appearing until the end of the film. There were just too many stories, so the result was that the main story was messed up. Plus, the scenes with Peter Parker showing his dance moves after his transformation into the bad side were VERY embarrasing. Is that the bad side of Spidey? Please...it's ridiculous.