If you are going for more than 3 days, for GODS SAKE get annual passes, especially if staying off site or in a non Disney hotel.
We paid about £40 more (between 4 of us) and saved well over €200 once there, and had so many benefits (and we can go again for FREE any time in next 12 months)
As heels has said, FP and magic hours a must (you get that with annual pass whether staying "onsite" or not.
Get to Ratatouille as SOON AS YOU WALK IN and get a fast pass (they are gone by about 11).
Leave your "money head" at the door, and worry about it when you get back. We saw SO many people grumbling & muttering about prices, that you could see they were ruining their own time there (If you ARE on a budget, take baguettes etc in rucksacks, they dont mind as long as you dont take the proverbial)
Rent/take a pushchair. Little one will be shattered !
Go do the busier rides (without FP or that you missed) at Parade time (if you have seen it already!), as everyone else will be watching that.
But most importantly : ENJOY IT !!!!