I'm from almost as far South Mississippi as you can get. About 50 yards from my front door and your in the Gulf.
You will have a great time on your 1st trip.
Will you be driving? For us it's around 9 hours, not so bad.
September will be a beautiful month to go. Waterparks will be open. They are open year round. We went in December and people were swimming in the hotel pool. Too cold for me, though.
There is so much information on these boards to help you plan your trip. A lot to go through, but great stuff.
Here's some of my family's favorites:
1. Stay on property. It sounds like you are doing that since you asked about the dining plan. The dining plan is GREAT! Not as good as it has been in the past, but still worth the money. Staying on property you can take advantage of extra magic hours and even have your souveniers delivered to your hotel so you're not lugging them around the park all day.
2. Fantasmic - a great show at Hollywood Studios. A not-to-miss for us.
3. Character Dining - Crystal Palace at MK, Akershus (princesses) at Epcot, Garden Grill at Epcot
4. Autographs - if you have children this is fun. Bring (or buy one at the parks) your own books and markers. I bring a small creative memories Disney scrapbook. I have the characters sign on one side of the page and the corresponding page I scrap my kid's pictures of meeting that character. I also bring the sharpies with the retractable points. They are thicker and easier for the "pawed" characters to hold, and you won't lose the caps.
5. Pin Trading - We started this when my daughter was 3 and she loved it even then. She still loves to look at her pins and talk about where she got them from.
Have fun and Good Luck with all of your planning!
