July is quite hot, but try not to plan on hating it. Getting to the parks early is a huge help, along with breaks in the afternoon -even if it's just resting somewhere in the park w/ the A/C and the evenings are more pleasant. Is this your first trip to WDW? You'll find it very different from other theme parks. There is a lot more to do inside. For example: Busch Gardens, Williamsburg is a beautiful park..but summer there is hardly bearable. There aren't a lot of things for families to ride together and everything except a couple shows is completely outdoors in the heat. WDW however, is designed with families in mind. So, there's a lot do to together and a lot of the attractions are indoor rides, which provides a respite from the heat.
For real? Whoa.