Come now; of course abilities matter. There's a reason the X-Men don't all have healing factors and claws as their sole powers; in the superhero genre, a generous variety of abilities is inherently more interesting than the dearth of same. Moreover, "what characters can do" inevitably shapes and defines "who they are". Just ask The Thing, or Nightcrawler.
You're taking me too literally. Someone suggested above that the reason DC movies don't work as well as Marvel movies is because of the different types of powers the DC characters have. My point is that this doesn't make sense as an explanation, because, while of course characters' abilities are relevant to the story just like any other character detail, they do not, in and of themselves, determine whether or not a story can be any good. There have been great stories and lousy stories about Superman, and there have been great stories and lousy stories about Spider-Man. It's not as simplistic as "Marvel has better powers than DC and that's why their movies succeed." That is just wrong on so many levels. There's no reason, in principle, why we couldn't have great DC movies and lousy Marvel movies. It's just the luck of the draw that the studio executives currently in charge of making movies based on Marvel characters have had a better handle on how to achieve it than the execs in charge of making movies based on DC characters. Ten or fifteen years from now, the reverse might be true -- we might be celebrating the brilliant work that's being done with Wonder Woman and Flash and the Teen Titans on film and lamenting that the glory days of Marvel films are so far in the past. There are no absolutes here.