Do you believe this diet is a good idea and will it work?

Yes as long as you eat a healthy breakfast as well and keep up the walking for 2 to 3 miles at least 5 days a week. Then definitely but you have to remember that it will take a while in the beginning to really start losing weight. Many people will give up on their diets because they don't see a significant change quickly enough. A good diet and exercise needs a chance to work but once it starts, you will be happy.