Just like January, February is a good month for low crowds and mild weather. The weather does tend to warm up a bit in February, but the evenings can be cooler than normal. Since there are no major Holidays in February, many families will wait until Spring Break or summer for their Disney vacation.
Most refurbishments and rehabs are winding down in February in preparation for Spring Break and summer. Hours of operation are basically the same as January with shorter hours and less wait times.
September is still one of the best months to visit Walt Disney World. The wait times for rides and attractions are shorter because most families with school age children have returned home to get ready for school starting up again. The weather is still quite warm, but still better than July or August.
There is a special event called “Mickey’s Not-So-Scary Halloween Party” which is held on select nights beginning mid-August through Halloween at the Magic Kingdom. It can be pretty crowded on those dates, but the “Party” takes place in the nighttime hours, so if you don’t want to attend the “Party”, just leave the Magic Kingdom early and go to another theme park.