Ahoy, Shannon...and congratulations on choosing Disney Cruise Line (DCL) for your family's vacation!
I suggest that you book your cruise for when your son is three so that he can fully enjoy the
Oceaneer's Club and
Oceaneer's Lab -- sometimes there are activities with a "Cars" theme involved in one of those two areas. If you cruise prior to his third birthday, you can reserve child care for him in
Flounder's Reef Nursery (
Magic and
Wonder) or in
It's a Small World Nursery (
Dream) for an additional fee.
As far as an itinerary to suggest for your child...I always start first with the parents. Where do
you want to go and what do
you want to do? Aboard Disney Cruise Line, your child is going to be sufficiently awed and amazed, and it will be unlike any vacation he has ever experienced. However, you are the one paying and planning for the experience and most likely the one who will remember the most about it. Therefore, you choose an itinerary which best suits you. If you've never cruised before, I suggest the four-night Bahamian cruise to give you a taste of a cruise experience and then you can venture out on your 2nd, 3rd or 4th time aboard DCL!
I hope this has helped you plan. Have a wonderful day and a magical vacation. Bon voyage!