Welcome to the Moms Panel, Aneta. Being a chicken myself, I was very anxious to answer your question. Both of the water parks have some very scary rides for us that do not like roller coast type adventures. They do have however, some wonderful areas where you can have an entire day of family fun without getting scared, even once.
At Disney's Blizzard Beach, you may want to try the lazy river ride, Cross Country Creek, or simply floating on a tube in Melt-Away Bay enjoying the sun and warm water on a hot summer day. If you're looking for something more active, try your hand (and feet) at maneuvering the obstacles at Ski Patrol Training.
I have to admit that Disney's Typhoon Lagoon is my favorite because of the awesomeness that is the Typhoon Lagoon Surf Pool. It is so much fun standing in the water and waiting for that six foot wave to burst out of the wall. The wave comes and gently lifts you out of the water; kind of like a little bounce. You can't help but laugh out loud because it's just so much fun! I could spend the entire day there. Typhoon Lagoon has other attractions too, including their version of the lazy river, Castaway Creek, and the Storm Slides that whoosh you down a twisting, turning slide into the water below.
If you'd like to check out more information on the water parks and filter the attractions by thrill level so that you can decide where to spend your day, please visit:
Typhoon Lagoon Blizzard Beach Aneta, the water parks are a great addition to your Walt Disney World Resort vacation and I know that whichever park you decide on, your family will have a "splashtastic" time!
Be magical,
Leanne T