Like other posters have said, aim for as high SAT scores as you can get. At this point, everybody here has the time to take the SAT at least once more this autumn if they feel like they need to.
Similarly, everybody probably has things they know they need to work a bit on. If you feel like you have solid scores at the moment, focus on other areas of your application you might be a little weak at - e.g. if you feel like your SAT2s will require a lot of studying new material, put the effort in there, or if you are lacking in ECs, try to pick up something new in the summer.
Finally, if you already have the results of your first SAT sitting, and are feeling a bit nervous, don't get too worried. It's hard taking an exam in a totally new format in a hall full of strangers, but things might be easier when you retake. Plus, now you know which bits gave you trouble, whether its timekeeping or the essay. There are always exceptions to the rules (I guess I'm one of them - I got just 630 in the maths part of my SAT, but somehow managed to get into Harvard), and admissions officers don't look soley at the SATs, though they are a very important part of it.
Reckon a high SAT score is 700+ in each area. Good luck!