This past fall our family made our first trip to WDW. It was awesome. I think my kids bring up Disney, a ride, a character experience, a dining experience, the parade or something almost every day.
Since it was our first trip I read everything I could on Disney. We were also on a budget and still managed to have an incredible magical time and I know you will too. My family stayed at POP. It was wonderful. Clean, great staff and my children loved the huge icons and the pools. The buses, food court and gift shop were great also.
Here are a few of my suggestions:
I took a folding hamper (I purchased it at a drug store for $3). I worked great to keep the dirty clothes in. Really helped keep things organized in a small room.
I took my coffee maker and a cooler. I pre measured coffee along with filter into individual baggies for each day plus a couple of extra. We drained and filled our cooler up with ice every evening. It worked great for us. We were able to keep milk and creamer as well as cream cheese, cheese sticks, fresh fruit, bottled water and sodas cold. We purchased a taller cooler with wheels so it could accomodate taller items. I put the cream cheese and such in large baggies to prevent water from getting into the food.
I did the same with laundy detergent and dryer sheets. I also took a stain stick and at the end of each day I would spot check our clothes and toss in the hamper.
Purchase Body Glide.

We found it at REI for around $7. The stuff is awesome. We put it on our feet and everywhere we thought we might experience chaffing and we never had a problem. It was very hot and humid in October. We were really surprised at that and we live in GA.
We did the dining plan and thought it was wonderful. It allowed us to have already paid for everything in advance as well as enjoy rest. we would have never eaten in otherwise. We did take our own breakfast foods (Granola bars, cereal, fruit, bagels, peanutbutter crackers) and a few snacks. We ate in our room every morning or walking to the bus and then would eat an early lunch (11:00) and eat dinner around 6:00.
If possible get out early to the parks (crowds are much lower in the am) and go back to your room for an afternoon break (nap) and then you are refreshed and ready for a long evening. My DD was 6 and DS 11 and they both were fine with taking a rest.
Pre purchase all of your film and batteries prior to WDW. Very expensive there.
We took a back pack with bottled water, a couple of small snacks, small hand held fans (1 each, diff colors), a few rolls of film and xtra battery as well as the kids autograph books and pens everywhere we went.
Well that is about it for my words of wisdom. I know you will have a blast. Just wish I was going too

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