I agree with a previous poster that the problem with 'Ohana is more with the hit or miss service. I seem to have more "misses" than "hits" over the past few years. The food has been good - not great, but okay, but I LOVE the bread pudding. It's making me hungry just thinking about it... And my kids do love it, it's a lot of fun with good activities for them to participate in.
If I may make another suggestion that you don't have listed, at the MK you may want to try the Crystal Palace. This is a buffet dinner (or lunch or breakfast) with Pooh and friends, probably perfect for your children's ages. The nice thing about a buffet with little ones is that you can 1) get your food right away, so they're not sitting around waiting, and 2) there is a lot more variety to choose from, including "typical" kids' food, so you're more likely to please everyone.
I think either one is fun, and a previous poster is right, you shouldn't base your decision on these reviews - many of my favorite places regularly get trashed on the boards, I can't think of a single restaurant that hasn't had bad reviews every now and then. Try for yourself and decide what you think!