tarponchik
Contributor
Considering that you only have one week, I would recommend to avoid anything that takes longer to get there. This leaves prety much only Grand Cayman, ABCs and Roatan of all great diving destinations in the Caribbean. Since your wife also needs a decent beach with sand and stuff, this takes the ABCs out. If you go to Grand Cayman, there are great beaches only in the West of the island (The 7 Mile Beach), so forget the East. Turtle farm is OK and it is also the only place on the island with decent shore diving. There is also horse riding nearby, and a couple of "wild" sandy beaches too. So, depending who's more important between you too, either stay at TF or their other place, Cobalt Resort, and let your wife entertain herself in the vicinity or drive to 7MB while you are underwater, or stay in some fancy resort on 7MB where she will be able to enjoy the beach right next to your place and you will have to drive to TF to dive (they are not too far and they have a shuttle, so it's not a big deal). Roatan has a decent beach where we stayed (Fantasy Island) and it also has some shore diving. As for the drawbacks, Grand Cayman has boutiques and cruise ships, and Roatan has sandflies.