Hi, Jamie! To start with, just about everything you'll need to know can be found at
www.disneyworld.com . You'll find information on each theme park, the water parks, dining options, and extra activities by going directly to the Walt Disney World website.
Things you typically need reservations for include table service dining experiences (character meals, signature dining, basically any sit down restaurant or buffet), dinner shows (Hoop Dee Doo, Spirit of Aloha, etc.), La Nouba (the Cirque du Soleil performance at Downtown Disney), and things like spa treatments, cruises, special tours, etc. If you have not made any dinner reservations, I would suggest browsing the menus at
www.allears.net under the dining section to see where you might like to eat. Many of the popular restaurants do fill up quickly, and I'm afraid you won't find very much available at this late date, but if you are willing to be flexible with your times and days, you might find something open.
If you can't get the dining reservations you want, there are plenty of counter service restaurants throughout Walt Disney World that offer more than burgers, so you won't have to worry about eating chicken nuggets your whole trip. Also, don't be afraid to ask the cast member when you call for your dining reservations (which you can do at 407-WDW-DINE) to suggest someplace to eat. They often know where the easiest locations to get into are.
You can also walk up to any restaurant podium and ask if you can be seated. Sometimes, they will have table availability due to cancellations and no shows.
Beyond dining, you'll find plenty to do at the four theme parks and two water parks, and you don't need anything but tickets to enjoy those!
Have a great vacation!