First of all congratulations because you are in for a most wonderful time, on what I certainly regard as the only true liner afloat. Queens Grill is something really special and if you get aboard about lunchtime I suggest you go there straight away. You will be greeted by the maitre d' and shown to your table but he has flexibility to move you, should you prefer a different location. As well as table d'hote there is a standing a la carte which includes virtually everything you could want including caviar, smoked salmon, lobster, dover sole, chateaubriand etc. The great thing is that you are treated as an individual, a thing that the main restaurant ( and that is good), cannot possibly do. The maitre d', your sommelier and your waiters are superb at making your visits special and it becomes something to look forward to on evey ocassion. Certainly we never bother going to Todd English or the buffet for any of the meals as the Grill is just so good. Opposite the grill is the grill bar, where afternoon tea is served and pre-dinner drinks. The former is excellent but we were not convinced about the atmosphere for pre-dinner drinks and if we didn't take these in our cabin ( you will be provided with free spirits and wines in your fridge) we went to the Commodore Club at the front of the ship, which has a cocktail bar atmosphere. Remember as an alternative to afternoon tea in the Grill lounge there is the Concierge lounge on deck 10, again for the exclusive use of Grill passengers and where you can arrange trips and get magazines and refreshments all day. You also have exclusive use of the Queens Grill deck with its jacuzzi(not that I ever was tempted by this)and loungers - a great place to rest or to watch entry and exit into ports from, as it is located at the back of the ship for good all round views. Do have a most wonderful time and you can hardly not, for it is a superb experience and I only wish I could afford it more often but have to ration it to once a year !!
You may wish to steer your wife away from Colombian Emeralds in Tortola! fantastic shop with great prices but she may just get carried away.. Seriously though, just take it all in your stride and enjoy. All the islands are very different depending on whether they are British, French etc. My only suggestion would be to do some research on the internet on the various ports of call and consider doing your own thing at each Port of call rather than going on the organised shore (unless you like being having everything done for you and going around in big groups). In the Caribbean , most of the main towns are a very short walk from the ship and you can easily pick up taxis. Doing your own thing lets you do exactly what you want although be careful to allow yourself plenty time to get back to the ship by the latest all aboard time - the ship wont wait for you if you are late back. Port Reviews is a good site for giving info on what there is to see and do and local transport etc. Have a wonderful time.
Best advice I can give you is to get to know your ship and your fellow passengers and things will soon fall into place. Read you daily programme and mark those things you want to do and see. Very bland, I know, but part of the enjoyment is the learning. Oh and ask for a dish that you really enjoy to be flambe' d at the table they used to do it so well in the QG enviously yours Id.