Of course you would not be crazy to dance ballroom. Your previous dance experience should be help you with regard to smoothness and grace. (Lucky you!)
In regard to how to get started, read through some of the other threads on this site. There is great discussion of the pros and cons of private lessons, versus group lessons, versus community college classes etc. There's also discussions on selecting an instructor. (I cannot stress enough how important it is that the instructor be up to date on the dances!)
What are your goals for this dance experience? Just to dance socially, or to compete?
Personally, I like to learn the very BASIC step from a video, then do group lessons, then work with a private lesson. Then go back and take more group lessons. Its a never ending adventure. I am a real stickler for getting everything "right" and have ambitions to compete. However, group lessons give the opportunity to experience different leads...which makes it much easier to be comfortable in social situations.
Since you have danced before, I am sure you will be very disciplined in your movements and all will come easily for you. I repeat LUCKY YOU!