Which essay topic should I write on?

Well, the second would be less "offensive", but I say you do the first, just not quite in the way you have it written. Instead of writing about you yourself being "Oreo" try to write about the stigma that is placed on black and white people to act a certain way, and if you don't, you're a traitor to your race. That will be a much more emotionally loaded and unique topic than the second.