Advise on charge offs/repairing bad credit

Hi I am new and looking for advice on how to repair my bad credit. Long story short . . . my first and largest mistake stems from was when I was married to my previous husband. He was unable to get financed for a car (not due to bad credit but not having any credit) so since we were married, had a newborn, needed a 2nd car in order for us both to work . . I put his car in my name. Fast forward about 3 years we seperated and his car was repossessed. At the time we worked together (yeah, horrible idea) so when we seperated I lost my job since he was my boss. Therefor I could not make the payment for him, and fell behind on my own car payments as well as credit card debt. Fast forward to the present time -- I managed to pay off all my credit card debt and any miscellaneous debt I aquired along the way ie. medical bills, student loans ext. So I am debt free. However -- I have a repossession on my credit, a bank charge off from when our join account was overdrawn and closed, and an apartment collection from an early termination since I had to move elsewhere since I had no income - and several reports of late payments even though the show as PAID.

I recently leanred I cannot get financed for a car (well Ican put who wants to pay 18% interest) as lenders are leary to be the first to make me an auto loan since the repossession. (Paid cash for the 2 cars I have had since then) My question is this, does it behoove me to go back and pay-off the charge off amounts that are on my credit report? Or is it best for me at this point to leave it alone and wait anouther 4 years until they fall off my credit report? Will my score improve if they show as paid? I have no idea what is the best option for me, but I currently have no bills aside from utilities (my husband pays the mortgage) and need to clean up the charge offs sine that is the only thing left on my credit. Suggestions???????