Hi Kandy!!
Congratulations on your upcoming Walt Disney World Vacation!!!
We love going to Disney's Water Parks. They are such a welcomed change of pace from the theme parks. Both Disney's Blizzard Beach Water Park and Disney's Typhoon Lagoon Water Park are great options.
With children I would probably recommend going to
Disney's Typhoon Lagoon Water Park. You honestly can't go wrong with either water park. Our experience with both parks is that Blizzard Beach has a bit more walking to it than Typhoon Lagoon. Each water park has areas dedicated to children of all ages, even the big kids (aka adults!)
If you are staying a Walt Disney World Resort, I would encourage you to go to Typhoon Lagoon on Wednesday, June 6th as the water park as Morning Extra Magic Hours from 8:00am-9:00am for resort guests only. I would recommend getting to the water parks when they open up first thing in the morning. We have always been able to get most of the water parks done right around lunch. This gives us time to head back to the resort and rest a little before heading back out in the theme parks.
Thank you again for your question and have a magical trip!!
Scott