Danielle, I love how you are beginning to think about your visit to the mouse well in advance. We Disney Parks Moms Panelists are all about planning!
May would be an excellent choice for a trip to Walt Disney World. The weather is warm and gorgeous and most families with school age children wait until summer to hit the theme parks so the crowds are manageable. September is also a good choice since many parents are reluctant to pull kids out of school so soon after it starts. Lines tend to be short, the weather sunny, and Mickey's Not-So-Scary Halloween Party is held on select nights. Early fall is also famous for often having everyone's favorite special offer- free dining.
Typically package and room rates are announced six months or so before the new year, so look for prices to come out for 2015 during the summer of 2014. To learn about discounts, the website Mousesavers is my favorite source. Also keep an eye on the
Special Offers page on the Walt Disney World site.
Please come back to the Moms Panel again during your planning process.