I dove cozumel last fall for the first time and loved it. From what I understand, Belize is supposed to be better, one of the top dive spots in the world. I hope to dive there one day myself.
If you have good or even half way decent buoyancy control, check out a cenote, I dove one myself and it was an unforgettable experience. You can't even see the water its so clear. It was a bit cold though, around 65F.
Report back when you return, love to hear how it went.
...and don't forget to exhale on ascent...
