As long as the hero isn't one who is based around being black like almost all of them are.
EDIT: About the only one I can think of at the time is James Rhodes. And yes I'd be fine if they made him white in a film.
James Rhodes is an interesting one because I seem to recall his non-white nature coming into plot points during his time as Iron Man, which arguably is a formative thread for his character (overcoming racial standards) - HOWEVER, since that was in the early 80s, I can't imagine they could make a plot point like that relevant in today's storylines.
But strangely, I still would find it very strange if Rhodey were white, and I'm not entirely sure why I feel that way.