Once a settlement has been paid out and injured party signed off on insurance can they still sue the injuring party?

Dear Debbie,   Without seeing exactly what you signed, it is difficult for me to answer definitively.  However, if you received payment for personal injuries from the insurance company of a tortfeasor, I can almost guaranty that you have released any rights you may have had to sue their insured for your injuries.  That is why it is imperative that you speak to an experienced personal injury attorney before you ever sign any documents presented to you by an insurance company.   Best of luck,   Chip