I feel so unprepared and trying to learn as much as I can about DCL right now. I really don't know much else.
Any help your willing to share would be greatly appreciated.
WE ARE REALLY EXCITED!!!!!!
Welcome ANT2304!
Like yourself, we're DCL rookies. Christine and I (Barry) are both 44 with our DS-8, DD-6, DS-2.75 so we're pretty close in ages with our kids. (Golly you started early!

Anyway, take your time to 'cruise' through all the posts here and get a feel for the board and the folks already here. They are a good bunch here with several veterans who have provided some good information on the cruises themselves and the activities. There is even a kids thread for this cruise (you can find the links several times in this thread).
As for excursions, everyone is different. Some are renting cars on the islands and touring, some are staying on board, others are just taking taxis or the Disney recommended transport to the beaches. Take your time. You still have a couple of months before you reach that 75-day window to actually book something.
Looking forward to learning more about you, where you're from etc.
One recommendation, don't post cabin numbers, hotel room numbers or other private information on the board. If you meet someone here that you really click with for your family, and you trust each other, then you can share that information including phone numbers via private messaging. (I've met one cruiser on this board who lives on the coast of Canada, but went to the same school as my wife! They don't know each other, but it will be interesting when we meet on board to see if they actually recognize each other.)