Bella
I'm sure you will have a fantastic trip and hopefully will get as much fun out of the planning as the trip itself.
I'd have to agree with the rest that, given your daughters ages then Magic Kingdom is a must and I'm sure they'd love a character breakfast or dinner (most girls love to dress up in their princess costumes for these to add to the excitement).
If you are only going for a week then I would say that the water park could be left off the list, given that the youngest may find it too much at 2, if your villa has a pool you'll probably find they are just as happy splashing around in that on your quiet days. It is advisable to allow a couple of days for chilling out with no specific plans even if you are headed to the beach the next week as the place is just so huge that it can't help but be tiring.
Once you've decided what sort of things you're looking for in your home from home if you put an enquiry out then I'm sure you'll soon have plenty to choose from which will more than please you.
Have fun looking and if we can help at all please ask.
You might also want to check out the threads on travelling with young children as there are many helpful tips in there as well.
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