I think your children are at the perfect ages to go to Disney. You will have soooo much fun. The best way to get the most out of Disney is to "know" Disney. A great book is "The Unofficial Guidebook to Disney." It is huge, but don't let that put you off. It is organized by park and easy to read.
All of the rides and attractions are given a rating. I think it's spot on. Ask the boys to read the book too, and circle/mark the rides they want to go on. Have them look at the ratings.
Use of Fast Passes will save you much time. Be sure you understand how they work.
Pack light. Really think about the amount of weight you want to lug around the park.
We think a sit down lunch, in air conditioning, can save your sanity.
Rope drop really is important. The lines are soooo much shorter.
Gauge the exhaustion of your family at regular intervals. Stop, sit down, and have something to drink. Re-group.
Have a plan. It does not mean you have to stick to it. Figure out your top 3 attractions before getting to the park. I actually number the order of what we will do. Again, you don't have to stick to this. You can change and jump in to a line that looks like fun. (Some folks will say planning is not a vacation. I say standing in the middle of the walk way trying to figure out what to do next is not a vacation.)
A few nights of your stay don't make dinner reservations. Just order a pizza and hang out by the pool. Having to get to dinner reservations every night, when all you want to do is stay in your bathing suit can get annoying.
You don't have to do fire works every night.
Sleep in one morning. (I know this goes against get there at rope drop.)
Really read that guide book before going to Epcot. It is hard to see what is around you, and you can miss some great attractions.