Run after 5 years of ACL tear. For that?

Hi I met with an accident 5 years back and my right knee ligament got nearly complete tear and a small crack on bone had happened. As docter suggested, it will be healed without surgery, I took rest a couple of months in plaster and after another couple of months physiotherapy, i got back to normal. But still I had a slight pain on my right knee or some times both knee. Later I forgot about it. Some times I uses to take weight and do climbing stairs and used to take my 2 year kid and walk. But I never feel any snap or dis location or discomfort apart from a very small pain sometimes. Right now I am thinking to go for an excersise in morning. I would like to walk and run. So can I do it with this injury? Will it make something worse? I have heard about after acl  tear there is a chance for arthritis. Will this excersise help for that? Please advise some tips if running and walking are fine. Please find the attached MRI report for more details. Thanks in advance, Jithesh.