It's absolutely obtainable. I would start out getting good, cushioned running shoes and put in good insoles. I recommend this to save your knees and hips if you're "overweight". Then I'd start with a walk/jog program: 1 minute jog, 2 min walk, 1 min jog, etc. for no more than 15 minutes to start. Build up slowly and listen to your body. If something hurts, more than just muscle soreness, then back off.

If you like having a plan, there are some good "couch to 5k" plans out there. Just google.

Good luck!