We'll be there from the 18th through the 29th. We stayed at the Wilderness Lodge around the same time three years ago, and it was very nice. The lines were very manageable and the weather was great. The parks were open late at night too. This time, Memorial Day weekend is early (5/23-5/25), and we are going to hit that in the middle of our trip. That will be peak time, and no fun. We are thinking that we might skip the parks on those days (or just go for early hours and enjoy the campground for the rest of the day).