Casa Del Mar. By far, the finest dive resort on the Island. I’ve stayed there so many times I think they named a wing after me. I remember when it was a Howard Johnson’s. No kidding. Hospitality is first class as is the diving with Del Mar Aquatics. Don’t worry about the drinking water, it’s so pure they bottle it and sell it down town. Every where is clothing optional, so get used to it.
Plenty of night life everywhere you look...downtown, uptown and the Casa it’s self. I’ve always said my "claim to fame" has been being tosed out of every famous trouist bar in the world and Carlos and Charlie’s is no exception. Be carefull going up and down the steeps. You’ll figure it out when you see the place.
Take a day off from diving mid-week and visit the mainland. Ferry from downtown Cozumel to Playa del Carman runs hourly till (I think) 10pm. Chetchen Itza is nice but for me the view from the ruins of Tulum over looking the Crib is breathtaking.
The long and the short of it is you can’t do Cozumel wrong and each time you go back there’s something new. That’s why I keep going.