Check out this Document from : The Credit Challenge to get an idea on how your credit score is calculated .
I also went through and cleaned up my report anything that was 7 years or older I disputed to have it removed from my report Public records like bankruptcy, judgments, tax liens, or foreclosure can stay on your report for up to 10 years. Again, if you see a public record showing up beyond ten years, you have a right to dispute it.
This is a great site to help you rebuild your credit yourself click here