I heard a discussion recently that I wanted to elaborate on. The competition of DC Comics and Marvel Comics at the movie theaters. There is actually a third comic company called Image Comics, but their movies are covered by Spawn which I barely like and I tried.
When these movies started the media conglomerates of today didn’t exist. All of the DC movies have been released by Warner Bros and at this point DC is owned by Time-Warner giant just as WB is. This will almost guarantee all future DC movies are WB released. Marvel doesn’t have a direct relationship with any studio. Many of the movies have been released by 20th Century Fox, the one major exception being Sony Pictures releasing the Spiderman films.
First I will list the respective franchises. I am not going back before the modern Superman films. The ones before then are before the modern movie blockbuster era. I will list them in chronological order (of first in series). I got some of this info from Wikipedia and some from IMDB, both are amazing resources.
DC
Superman 1-4 (1978-1986)
Supergirl (1984)
Batman 1-4 (1989-1997)
Catwoman (2004)
Batman Begins (2005)
Superman Returns (2006)
Marvel
Blade 1-3 (1998-2004)
X-Men 1-3 (2000-2006)
Spider-Man 1-3 (2002-2007)
Daredevil (2003)
Hulk (2003)
The Punisher (2004)
Elektra (2005)
The Fantastic Four 1-2 (2005-2007)
There are a few ways to evaluate the collection of movies against each other. One way is to compare total grosses or more currently total DVD sales. That is a tough comparison since there are different numbers on either side. Along those lines the rankings in all time top 100 might be a good check point. As far as critical acclaim goes most of these movies are polarizing, with those either liking or disliking almost all these movies.
The top 100 all time lists 8 of the movies from these superhero franchises. There will probably be 1-2 more shortly with Superman Returns and X-Men: Last Stand. The two Spiderman films have been the biggest hits of late, both in initial weekends and staying power.
One thing I think that can be universally accepted is that the franchises that made it to three or four movies in length fell apart. It seems that the third movie begins the downward trend and the fourth hits rock bottom. The best example of this is the original Superman and Batman series. The third Blade and X-Men films aren't horrible but aren't as good as earlier films. Hopefully the third Spiderman film will not follow this trend.
It is interesting to note that with these movies there seems to a true hit or miss mentality. The good movies are really good and the bad movies are really bad. Look at Supergirl and Catwoman for DC and then Daredevil, Hulk and Electra for Marvel. I guess Fantastic Four isn't horrible but it leans more that way than toward being a classic.
I would say DC had the early lead in the race. However they burned out for a while by running their franchises into the ground. In the interim Marvel stepped up and re-invigorated the genre with Blade, X-Men and then really hit it big with Spiderman. Now DC is back in the game again with their re-imaginings of their original franchises Batman and Superman. Hopefully Marvel doesn't fall into the same trap that DC did and at the same time I hope DC doesn't ruin their franchises again.
The worst thing must have for DC and Warner Bros when they began a 7 year drought beginning with Batman 4 and ending with Catwoman. That is a really sad period of time. Hopefully it won't be repeated any time soon.

NERD!! ;)