
Welcome to the Dis. Whoa! This Sept? That won't give you much time to plan, but it's doable. Crowds will be OK, but food and wine festival plus
free dining add to the numbers. It is still very hot and humid. Afternoon showers/ thunderstorms are common .
Because WDW is so big, and because the parks aren't side by side like DLR/DCA, you'll need to spend a bit more time planning. The Halloween parties at MK are also going on, and they're hard ticket events , so you'll need to plan around them as well.
You don't mention how long you're staying, whether you're staying on site, or if you have Park hopper tickets. These matter when planning, most especially when it comes to EMH and FP bookings.
I'd recommend you start by planning which park you will go to each day. A good resource for this is easywdw.com. Their crowd calendar includes recommended parks for each day as well as a day by day overview of things that may affect crowds and park touring.
Once you know which park(s) you'll be in each day, you can make your ADRs for any TS restaurants you want to eat at. I like to make ADRs for the park or nearby resort I'll be in during that time period. This saves a heap of transportation time. The Restaurants forum can help with questions. Allears.net is a good place to chekc out the restaurant menus.
You can make FPs 60 days in advance if you are staying on site (provided you have a ticket attached to your
MDE account). If you're staying offsite, you can't make them til 30 days out. There is a sticky on the Theme Parks board that deals with FP questions.
Good luck with your planning. Hope you have a great time.