Hey, DeeDee!
Well...congrats on planning your first Disney Cruise -- you're sure to be a pro at Disney Cruise Line (DCL) vacations once you get this one under your belt! (Warning: DCL vacations are even
more addictive than WDW vacations!)
As far as choosing a deck level, it's really going to depend on your personal preferences, your stateroom category and when you book your reservation (availability). For instance, some guests like to book lower level decks in the middle of the ship to avoid the feeling of movement when they're in their staterooms. Mid-ship is desirable for some because of the easier access to the main stairs and main elevators. Therefore, stateroom categories near mid-ship may book quicker than other areas. Yet, these areas (especially during evening hours) can become congested and noisier than stateroom areas located Aft or Forward.
You can take a look at each of the
ships and click onto Deck Plans to take a virtual tour and see which decks host various activities. Depending upon your personal preferences, that will be your best resource in terms of areas you would like to be near and others that don't interest you. I hope this helps you plan!
Have a wonderful day and a magical vacation. Bon voyage!