The running probably won't make it feel better but doing leg exercises will definitely help! A big stabilizer of the knee is the hamstring... Sqauts, Straight Legged Dead Lifts, Leg Curls, and lunges are all excellent exercises for working the hammy's. You'll also want to work your Quadriceps. No guarantee that this will alleviate your pain (especially if you have some torn cartilage which would be hard for your doctor to detect) but it will certainly stabalize the knee. Good luck!