Have any moms out there gotten their bodies back?

I have four children. I am currently in the process of trying to lose weight, and I am on a calorie restrictive diet. I am eating 1500 calories a day, and walking 2 miles a day. I have only lost 20 pounds in the past year doing this, and I would like to step it up because I am still at 212 pounds and unhealthy. I am wondering if there are any moms that have lost the weight and toned their body back up. I am looking for ideas as to the best exercise or nutritional steps to take to bump up the weight loss. I don't mind taking it slow, I would just like to average 1-2 pounds a week and get healthier sooner. My youngest is 4, so I am not nursing or recovering. I have just gotten to the point where I am ready to turn my health around. Thank you all for your time.