I've been at WDW in February, April and July - and believe it or not, July is the best. February and April had school breaks + large crowds. In the summer, kids have two months off so everyone doesn't have to go at the same time!! Yes, it's hot, but the little afternoon showers take care of that and, on July 5th, a lot of people leave. Last July, we went through all the parks, wait times were maybe 20 - 30 minutes
at the most all week. We got a reasonably early start each morning (but not there for park openings), had lunch mid-afternoon and had our second wind by about 4:30 when a lot of guests leave to get ready for dinner. I'm convinced that this works if you pick carefully which parks to go to one which day of the week. A couple of the guidebooks have lists of recommendations. This summer will be the third time I've planned this way and we'll be getting in on 7/2 so we'll see if it holds up this time.
