Need Suggestions for Exercise with Lower Body Injuries

luvopera

I am 45 years old, 5' 7", about 200 pounds, and not in the greatest shape anymore. About a year ago, I was doing 30 Day Shred and then moved on to Insanity. I hurt my right knee and right foot and now cannot do either of those exercise programs. I cannot afford the surgery I need on my knee yet so I am stuck with a lower body injury for a while longer. I would love to have some suggestions on types of exercise or exercise programs I can do with a bum knee and foot. In spite of my weight, I'm a tough girl and want something to challenge me. I have some free weights and thoughts about that but don't really know where to begin.

Any suggestions out there?