Hi and Welcome!
My advice - read, read, read everything you can get your hands on, but NOT this board as your primary source of info. First, get the facts on Disney World, then come here for opinions, ideas, etc. If you start here, you'll get more opinion than fact and it will make it difficult to truly plan.
You MUST have some sort of plan ahead of time, even if it's only what parks to go to on what days. Check our **************.net or easywdw.com for free information and advice on planning.
Watch the Disney Planning DVD, look through the Disney website for maps and information on each park. Understand it's huge!
Take your time, do some research and you'll be fine on your own.