Based on your medical history, I don't know that we'll be able to give you specific exercise advice. I'd recommend talking to your doctor about it, and they might even be able to give you a referral to see a physical therapist who can create a set of exercises specific to your needs (to address your joint issues).
The good news is that when it comes to weight loss, the majority of your progress is going to come from diet, not exercise. So even if you can't be as active as you'd like, you can still lose weight consistently if you're tracking your food and staying in your recommended calorie and nutrient ranges daily.
Hope that helps,
"You may have a fresh start any moment you choose, for this thing that we call "failure" is not the falling down but the staying down." Mary Pickford
"No matter how slow you go, you are still lapping everybody on the couch."