That is the same week we usually go. Normally I would say that the week you have chosen would be the best week at WDW for a summer trip. The earlier in the summer you can go, the better. This is still, probably true, but 2009 is an extremely busy year for WDW. I was shocked at the Spring Break crowds vs. years past (they were so heavy I forgot it was spring break and thought it was Christmas!). So expect crowds, fast pass everything and I would say it would be worth investing in the unofficial guide so that you can go online and use the crowd predictor…they are usually right on as far as crowd levels go.
Disney World Crowd Calendar — The Unofficial Guide to Walt Disney World