Marvel Comics
What can you say about Marvel, they have dominated the film industry since 2008 and show no signs of slowing down. They brought credibility back to the genre and the result has been a string of high quality films with many more on the way.
DC Comics
They may not be on the level of Marvel in regards to big-budget studio films, but DC Comics has some of the most famous characters in the genre and is starting to solidify their footing in the full-feature film business.
Other Comic Brands
Marvel and DC Comics may dominate the comic-book film market but they are not the only ones in the business and over the years their have been many great characters and films from smaller comic-book companies, with many more slated for the future.