About a 2 hour drive on I 4. Crescent beach is near Siesta key I believe. It has a beautiful white beach but it is crowded. We have driven from Sarasota to Disney and the drive is not too bad. There is alot traffice close to Orlando.
it's our favorite beach in all of Florida, about two hours from WDW but interstate the whole trip. there's a snack bar and ice cream stand for lunch, and plenty of restaurants in the village for dinner.