I went two years ago to W. Car. for the first time and I am hooked. I am getting ready to go on another in Jan to the same place but i traded key west in for montego bay instead. My brother is going with us this time and he is a first timer as well and he has been reading these message boards, and like you are getting over the nervousness and becoming very anxious to set sail. He as well can not think of anything else except this cruise).
Grand Cayman - we did stingrays and loved it so much we are doing them again. This is a must do.
Cozumel - we heard that theChankanaab Park is a must do, so we are going to book an adventure called Sea Trek Helmets. This is a 25 min walk 20ft down under the water. I heard that this as well was a must do.
Last time we went we booked everything through the cruiseline because we made plans and sailed almost 2 weeks later. This time have had time to look into websites and have heard that there are so many different excursions that you can book on your own and these usually take you away from the "cruise crowds".
Sorry - probably more info than needed :-) No worries - you will have so much fun!!