And a word about SAT's in admissions: When applying to a public school, SAT's and GPA's are worth about the same, combined probably 80%-90% of what gets you into that school. The rest is your personal statement. Its crap, but they have a lot of applications. Even in smaller private schools, your SAT and GPA will still be weighted about the same.
My advice - go to your college advisor. Or dont, as most college advisors know frighteningly little about actually college admissions, just due to the rapid rate of change each year. Anyways, find out if the school you want accepts ACT instead of SAT. If so, do that. While still having some of the problems of the SAT, the ACT is, in my belief because of how new and "un-devolved" it is, better at measuring your scholastic aptitude.
And also, remember that SAT and GPA scores by no means determine your intelligence. Lots of smart people I know had terrible grades, and I know even more people who get 4.0's and are completely clueless.