I recently had a conversation with two old school friends, both of them brother's one of who Cruises on a regular basis (the younger one about 42) and the other who always returns to the same Hotel in Eygpt every year, while talking to them it was obvious that the older brother would not try cruising as that was giving in to younger brother and was a little put out when I also pointed out the benifit's... I had betrayed him and we are the same age!
Mostly it was lack of knowedge too that had deterred him....so this is what I said to him.

Hitting the open water is an experience in itself. The big—er, enormous—Ships, the 360 degree horizons, the different ports of call. Of course, there's also plenty to do on board. You can choose from fitness (golf, rock climbing, snorkeling), poolside spa treatments or a few classes in cooking or wine tasting. Pick a cruise for kids, for food, for nature-seeking—whatever. Then dream up your destination: Alaska? The Caribbean? Mexico? Jamaica? After that, pack your bags and there's very little else you have to do. Let the crew members take care of you while you're on board. Your biggest decision may be what to do when you disembark for a day—but then again, many cruise ships also offer on-land tours. So, leave the backpack and maps at home, work up your appetite for the culinary delights on board and get in on the experience at sea...