OP - I have been there 9 times, I think. I always get fuzzy, as a few of them were so close together. I try to remember by the hotel...
Anyway - I used to think I knew a lot about WDW. I went there a bunch in the first 6 years I was married. I'd buy a new Birnbaum's guide ever two years. I always had friends asking for info. and advice. THEY thought I was an "expert."
**Ahem** Then a new friend mentioned the book "Unoffical Guide to WDW," and I read it. And I found this board. And it was quickly evident that I only knew 10 - 20% of what was available to know!!!
And it has never been the same.
Did I have a blast all the other visits? YEP. I never left disappointed [albeit we went off season.]
Now that I know that I don't know all that I could know, I must say, there is a certain degree of STRESS to be had!
So - with only a few days until your trip, I would encourage you to keep in mind that you CAN NOT do everything at MK in your upcoming trip, BUT
you CAN have fun with everything you DO get to do.
Arrive early.
Read up on how Fastpasses work.
Search "Best days for WDW" and also poke around the websites for suggested plans of attack for your parks.
Make sure your camera batteries are charged. Dress in layers.
And have lots and lots of fun.