Hi Ann *waves* Welcome to Cruisemates
I looked at the layout of the ship. It looks like all Ocean Views from Majesty deck on down won't have any problems with obstructed view. basically the lower down the ship you go, the less expensive the cabins get. The least expensive cabins are located on the bottom deck and are the inside cabins. Sometimes you can get great deals or upgraded if you choose to book guaranteed but that will not ensure that you will have your cabin next to whom your traveling with.
I would suggest you get travel insurance. You never know if something will come up and you don't want to lose the money you paid for your cruise.
There are always extras that you will pay for on your cruise. These will go on your ship board credit line that you pay when you settle your bill at the end of your cruise.