Hi aastha3344gmat,
As far as your GMAT Score is concerned, GMAC has publicly stated that the Official Score that you earn on Test Day is within +/- 30 points of actual ability. Your 2 Official Scores are essentially identical - and they show that you performed in much the same way both times you took the Exam (580 +/- a few points). You handle certain aspects of the GMAT consistently well, but you also make certain consistent mistakes. If you want to score significantly higher than 580, then you are going to have to make some fundamental changes to how you 'see' (and respond to) the GMAT. In simple terms, if you continue to study in the same ways as before, then you will likely earn the same general Score.
The process of applying to (and ultimately attending) School will require a big investment of time, money and energy on your part, so you really should make sure that the Programs that you apply to match your career goals/needs. There are a variety of factors that go into selecting the Schools that you'll apply to. Instead of just applying to Programs in which you might have a good chance to 'get in', here are some other things to think about:
1) Is there a particular company that you want to work for or industry that you want to work in? Certain degrees are more appropriate than others if you have a specific career goal.
2) What do you want your Degree to do for you?
3) Do you want to go to School full-time or part-time?
4) Are you willing to relocate? Are you comfortable with working through a program that is primarily online?
5) Are you going to be applying for scholarships?
Etc.
It's okay if you don't have answers to any of these questions just yet, but you really should try to define all of the important variables in terms of your goals, so that you can tailor your entire approach to getting into the best School that matches what you're looking for.
GMAT assassins aren't born, they're made,
Rich