October-November is my absolute best time to plan a Disney vacation. Between the weather being terrific, and lower crowds during the week, I highly recommend this time of year. We have been down there just about every season (hated early summer though) and we must have gotten lucky, the crowds were really super super bad, but the weather PLUS waiting in line for ANYTHING made for a grumpy Deb! LOL Its funny, during our October-November time frame, we never encountered tour groups either
Our off season discovery coincided with an anniversary trip and we were amazed there were no crowds, tour groups etc...now, we have been going for 30 years and Sept and Oct. crowds have increased dramatically over the years. One trip many years ago we did Tower of Terror four times in a row walk on without stopping for a line. Could have done it more, but started to get dizzy. Early Sept. remains less crowded than Oct. but weather is much better in Oct and Nov.
Went once in July, 1996...won't be doing that again, although I would brave the crowds once for July 4 fireworks if the opportunity presented itself.