Which K and def to start?

Go with Cards defence, because they do let up a good amount of yards, but in fantasy its more important for things like interceptions, sacks, forced fumbles, safetys, etc. And the Cards have very quitly piled up tons of sacks and interceptions. Go with Kris Brown for your kickr, because the Texans now have Matt Schaub and Andre Johnson, so they can move the ball downfield, but can't always finish it off in the red zone because they have no running game, epieccaly with Ahman Green out.