I've got one of those - the other one is more laid back. My best piece of advice is to stick to whatever discipline technique you have at home. I know, a lot of people don't like to do that on vacation but it has been my experience that sometimes the really high-spirited and SMART ones see the opportunity to take advantage of the situation (ok - so maybe that's just my own dd) if they sense that it is a 'special' occasion and the same rules do not apply as home.
So, with us - if we enforce the rules one or two times early in the trip - she gets the hint that good behavior is expected at WDW too and it makes ALL of our trips way less stressful and more enjoyable.
One example - dd decided to have the mother of all meltdowns our first time in line to go to MK on our day of arrival (just after a 2 hour nap - so she was NOT too tired or anything). With the nice audience onlooking, she decided she NEEDED to have juice (which I never carry in the diaper bag - only water so it was totally for the audience factor) - and when I said no, she had a meltdown. We did what we would have at home - ignored her (well, at home she would have been allowed about 1 minute to settle down herself before being sent to her room so all of us aren't disrupted by it, but, this, in line for a bus, was not an option). We got lots of nice looks (being sarcastic here- a lot of them were not nice and had the 'I can't believe you're dragging a tired kid back to the parks' look to it), but in a few minutes, she settled down and said 'can I please have some water?' - so it was settled - she did not get any special treatment even though it was a vacation with onlookers.
Anyway - just something to think about beforehand - one 'timeout' on a nearby bench or going in early from the pool due to bad behavior might make your little ones angels for the rest of the trip!
Best of luck and you'll have a blast!