Hi Nicole,
What a special trip you are planning! It is so fun when those of us who head to Walt Disney World often are able to share it with people who are special to us. I am sure that your boyfriend is going to really enjoy this trip and the care that you are putting into planning it!
Fall is a great time to head to Walt Disney World. The weather is starting to get a bit cooler than the heat of summer, but it is still warm. There are also great activities at Walt Disney World during the fall, including the
Epcot International Food & Wine Festival. This wonderful event includes kiosks with food from around the world, culinary demonstrations, concerts, and so much more! It will be happening during both of your possible trip times, and I definitely suggest that you check it out.
The weather should be similar during both of your trip time possibilities, though obviously just a bit cooler in November. I would also anticipate crowds being a little lighter on the October dates as my guess is that more schools will offer time off for Election Day and/or Veteran's Day rather than Columbus Day. Given those considerations, I think that I would lean a bit toward your October dates, although I think that they are probably pretty even and you cannot go wrong with either of them!
I hope that these thoughts are helpful for you, Nicole. Have a wonderful time planning your magical vacation, and please do let us know if you have any further questions.