Hi JayeeCruise, and welcome to CruiseCrazies. Lots of great people on this forum with answers to lots of questions.
I have never sailed Guarenteed, but I have seen lotsof people write about it on the boards, and almost every one of them were satisified with it. It means that you are guarenteed to get an Oceanview cabin on your cruise, That is the lowest grade you can get. You may actually be upgraded to a better cabin for the same price, but never count on it. The price of a guarenteed cabin is usually less than booking a specific cabin. The general rule is book a guarentee for the worst cabin that you are willing to take, and maybe get upgraded. You may or may not have an assigned cabin as of now, but there have been previous threads telling how to find out if you have an assigned cabin.
Again welcome, and please post often.
Howard