Hi, fellow Tennessean, Gayle! Last year, the dates for the 2010 Mickey's-Not-So-Scary Halloween Parties were released on May 21st (thanks to my fellow Moms Panelist, Allison V. for that helpful tidbit). Be watching the Disney Parks Blog for information. You can find it
here, and you can also subscribe to their email. In the meantime, until the official announcement, you can make predictions based on the days the Magic Kingdom closes at 7:00 P.M. That's a good indicator it might be a Halloween party night. Keep an eye on the blog and
this link.
I checked the Walt Disney World website for you and found that during your travel window Fantasmic! is scheduled for two presentations. On October 2 and 6, 2011, it is set for 8:00 P.M. As noted on the website, these times are subject to change, and you should always consult the Times Guide upon entering the park. I hope this helps you. Have a Magical vacation and happy planning!