Hi, Kathleen! Congratulations on your first trip to WDW, and you can start the countdown now! Sometimes, we'll mark the days off on the calendar...or we'll make a paper chain and let each child take turns tearing off a link each day. That really makes it seem real to the little ones!
After a long drive, you're going to need a little recuperation time before you hit the parks the next day. Therefore, consider checking in and getting settled into your room first. Then, explore your resort and take a dip in the pool. My kids (not knowing what to expect from the parks) used to look longingly at the pool as we zipped to the parks. Then, we finally learned to spend the first day at the pool so that they felt like they weren't being slighted with pool time.
Depending on where you're staying, you can make a dinner reservation for a restaurant at your resort, or you can take WDW transportation to
Downtown Disney to enjoy restaurants, shopping and entertainment there. That's my #1 choice for a day when we don't have tickets to the parks. There are some great little rides for your toddler such as a tiny carousel, and the street entertainment and stage show at night is wonderful. Try to book reservations at the Rain Forest Cafe or T-Rex Cafe...your boys will love the special effects, and you'll love the food. Then, there's the Lego Store, the World of Disney store and many other specialty shops that will delight your entire family.
My other ideas would be to schedule a dinner at another resort that peaks your interest and then rent a pontoon boat; take in the Boardwalk Area by having dinner and renting a surrey for a bike ride around the lake; or travel over to Fort Wilderness for Mickey's Backyard BBQ and/or Chip n' Dale's Campfire.
Maybe this will give you some good ideas. Have a wonderful day and a magical vacation!