More importantly, please don't build web browsers that give nitwit web developers the option of hijacking scroll (or control keys!!) in the first place.
I use the web to build applications and very much need to set scroll points and capture key input thank you very much.
I'd really rather you didn't do that, since it makes using the web as the web so annoying. I think we really need to fork the web and let "browsers" specialize in one direction while the "client/server application platforms" go another.