You don't have an option for June. We lucked out the last two years with awesome weather. '04 wasn't so nice, and it wasn't just because of the rain. We can keep our fingers crossed, but if I had to do it all over again, I'd go with June. More people out of school, most Weddings take place in May so there'll be less people complaining about that, and the weather is bound to be warmer. I'm with Jim, and think 2 weeks AFTER Carlisle would be perfect!
Memorial Day weekend = Crazy traffic, jacked up gas prices, lots more cops out and about, and the chance of some places not being open such as a track.
Oh, and whatever you do, no baby blue t-shirts or I'm not coming!
Mark
