I like October. Sometimes you get showered, but it’s good weather, good company, and good fun. You can move through rides often without any wait in the evenings (try during the parades) and early morning, taking a relaxing break in mid-day. Stay in a cheaper on-property place if you can (there are saome deals that time of year, and avoid the fancier hotels.
You should just wait for me to go. I have what is known as the “line curse”. No matter where I am, if I wait in a long line, by the time I get to the front, there is never anyone behind me!
Go when the park opens at 9 am
Went to Universal Studios/SeaWorld/Disneyworld with my wife and daughter last year. My extended family was there too. They all went as a big group. My wife and daughter got up early each day–quickly got to the park and had a great time. Went on all the rides right when the park opened, some of them we even went right back onto the same ride since no one was in line.
At 11 or 11:30 we stopped riding–had lunch and were back at the pool by noon—perfect! My family on the other hand got there by 11, stood in line for everything, came home grouchy and tired! Rode easily 1/3 the rides we did.
I really think the best option is go early and get out before it gets crowded!
Something else: DO NOT Go to the Magic Kingdom monday, then go to Epcot tuesday, then Disney-MGM studios wednesday. Almost everybody does that. Do them in some other order.
Or just go off-season. There’s barely anybody there anyway, I highly recommend it.