Hi Christine,
April is a great month to visit Walt Disney World and you are going to LOVE the Boardwalk. I recently stayed there myself for the first time and just adored the turn of the century theming, beautiful rooms, and the convenience of its location to Epcot! You have chosen very wisely.
Typically, the weather in April is quite lovely. Average temperatures are lows in the 60s and highs in the mid to upper 80s. As is standard with Florida, you can never rule out the possibility of showers. However, the average rainfall in April is minimal compared to the summer months, Florida's rainy season. It is always good to at least pack a light jacket for the evenings!
Spring can be a very busy time in the parks. However, with Easter being earlier this year and most Spring Breaks around the country usually falling in March, you will probably find this week an ideal one in the parks. Crowds will most likely be light to moderate.
Don't forget to check out the
Epcot International Flower and Garden Festival going on at that time. The topiary displays throughout the park are amazing! It is definitely a must-do since you will be so close at the Boardwalk!
Have a magical time and feel free to stop by and ask me more questions!
~Allison L