Exercise is great for a healthy body. However in your case with your weight along with your joint pain and gait abnormalities, it would be more beneficial to alternate with walking in water and cycling. A five day plan might be as follows:
Monday: Cycling 15-30 minutes
Tuesday: Walking in water 20 minutes
Wednesday: Cycling 15-20 minutes
Thursday: Walking in water 20 minutes
Friday: Cycling 15-30 minutes am
Walking in water pm
Other exercises would put too much strain on your joints such as walking on a treadmill or walking around your neighborhood. If you are trying to lose weight and once the weight comes off, walking on a treadmill may be an option as well.
You can also do strength training exercises with 2-8 pound weights that work out your upper body.