Chad:
Typically both October and November bring milder weather to Disney World. Of course, November can be chillier than the first week or so of October and also decrease your chance of facing hurricane-related weather.
If you're looking for both mild weather, lower crowds and cheaper rates, I suggest looking further into November as October is usually Regular Season and, with Columbus Day and the opening of the
Food & Wine festival at Epcot, can see some spikes in crowds, especially on the weekends.
Our family has visited the first week of November and found the parks very manageable and the weather just warm enough for an afternoon in the pool. Best of all, you'll find Value rates during several weeks of the month except for Thanksgiving week. And a good rule of thumb is that Value rates typically mean lower crowds at Disney as supply and demand determine costs.
Wishing y'all a magical vacation!
Whitney