You can get free copies of your credit report, one from each credit reporting agency, once per year. A credit report does not tell you your credit score, just what lines of credit you have under your social securtiy number and their status (paid, late, collections, etc.) Your credit score can be determined by many different formulas, and it just depends who is checking it what method they will use. Not everyone will interpret a credit score the same way either. I'm pretty sure you can get your score included with a credit report for a small fee, or you can sign up for a credit monitoring service and keep an eye on it that way.
As for the past and how it affects your credit today, the big picture usually matters more than isolated events. Are you/he always late paying bills, or spending up to/past your credit limits? Those types of activity are the biggest red flags to potential landlords, not what happened 7 years ago. It might still affect your score though.
All that said, you definitely have a chance at getting out. Keep looking around, there are probably a lot of places that might not even check your credit. I'm not sure how the housing is down there, but here in Chicago there are two- and three-flats where landlords live on one level and rent out the others, and lots of them don't check credit. For the ones that do check, just be honest about your past and go from there. Don't give up!