I never read the Marvel Comics when I was in comic book mode. The only films I've seen of theirs are the first Spiderman and the first two X-Men. I know of some of the other characters though, due to a crudely animated series of 5 minute cartoons in the 60s. Each one just had one hero, like Captain America, Thor, Hulk, Iron Man, Spiderman, and Submariner. They each had their own theme song.