Hi Shaer!
If I were you, I would absolutely consider adding the regular dining plan to your package. Since you will be staying for five nights, it will cover your five sit down meals and will give each of you five counter service meals and five snacks.
I enjoy the dining plans because with them the majority of your meals are paid for in advance and they can really save you money in the long run. Every trip we take with the dining plan, our actual food costs are much more than what we paid for the plan. Since the meals are paid for in advance, you don't have to worry about prices and everyone can just order what they want. It makes the vacation much less stressful in my opinion.
To get a better idea if the dining plan would be a good value for you, I would suggest looking at the menus at
www.allears.net to get a basic idea of the prices at the restaurants you've selected.
I hope you have a fantastic first trip to Disney with your sons!