We have not been there, my DD rides at a local stable, but I know families who have gone there, and had good things to say. It is about 15 miles from WDW - off of Hwy 192 - the area that has all the "other" tourist stuff!
From the website -
Trail Riding:
We have three types of guided trail rides available depending on what you're looking for. The first is our Nature Trail Ride. This is a basic ride that is a nature walk on horseback. No experience is needed. Anyone six years of age or older can ride on their own horse. Any child five years of age and under can ride with their parent or guardian. If you are looking for a nice easy going relaxing ride then this is the horseback ride for you. It lasts about 45-50 minutes.