Hi Dave - We went last year for our honeymoon (Oct. 12 - 19). It only rained one day and I thought the crowds were not bad, though we'd never been there before. MK is always the most crowded, I think. There were a couple days (maybe due to Food & Wine Festival) when the World Showcase was pretty crowded. All in all, we decided it was our favorite time to go. We bought our tix for MNNSHP way in advance, and I know Halloween night sells out fast. The weather, overall, was great though still a little muggy. We never wore pants or a long sleeve shirt. Maybe someone else can compare the crowds to September for you. Have fun!