Marvel or DC?
As someone who was quite serious and passionate about comic books for more years than I'd care to admit, I would have to say it depends. Are you talking about the books or the film adaptations of them?
For the most part, Marvel has better titles, but does a poor job translating them to film. Some of the Marvel adaptations are truly painful to watch and one (the first go at Fantastic Four) was so bad the studio never released it. Sure they say now they never intended to release it, but they spent 1.5 million to make it, so you decide.
And continuing the theme:
Captain America: With Guns or Without?