We prefer eastern over western Caribbean but our reasons are a little fuzzy. It seems to us that eastern is more exotic, with a completely Caribbean feel. Ports like St. Thomas and St. Maarten are so different from our everyday life and it's fun to look at the globe and see how far we've traveled.
The western cruises are good as well, and sometimes they're cheaper. They usually have several stops in Mexico and perhaps Grand Cayman or Jamaica. Right now the Mexican areas are off limits due to the hurricane, but they might be coming around early next year. I don't know.
Our favorite time to cruise is late January to early March. It's usually cold in the U.S. and although I live in a fairly warm state, it's refreshing and different to sail in the tropics.
You said you were a wanna-be. If you haven't cruised before, go for it. You will have the time of your life! You'll be recharged, wonder why you didn't do it sooner and hunger for more.
My advice is to pick a newer ship, although sometimes older is wonderful too. Some of our cruises were slightly better than others, but we've never been on a cruise we didn't love.