I recently gave my SAT - 1, and got a score of 2100. How good would my chances be in the top universities?

I got 800 in math, 680 in writing, and 620 in reading. Will reading really dampen my chances? I aim to get around 750 in my science SAT-II, so would that be enough to make up for the SAT - I score, or should I give it again?