I agree with buffettgirl--they are VERY different.
We have done both, and Love both for different reasons.
Hoop Dee Doo is fun and the food is good too. The first time I went was a million years ago with my parents, I thought I would HATE it because I was a teenager, and dinner shows weren't "cool" but I ended up loving it. Ive been back twice, and my Fiance was with me this past time, he also wasn't too sure he'd enjoy it but he really did.
WCC-has great food and the CMs are awesome!! There are more options for what to choose (though we suggest the all you can eat skillet), and no Show, but there is entertainment all around you.
If I had to choose for myself, I'd go with WCC. But its all about the type of experience you are looking for!