Oz the Great and Powerful will the first up. My way of thinking has always been that there's something good about every movie. To stick with that I'll tell you what I liked first and then what I didn't like.
What I liked:
It was very pretty. The effects (almost all special and seemingly very little practical) and sets were all pretty cool. The women in the movie were all very pretty and their costumes were as well.
Zach Braff was good.
The opening titles were neat.
Lastly I think it tied together well with The Wizard of Oz. It really set up that movie quite well.
What I didn't like:
James Franco. Honestly there has to have been someone else who could have done a better job. He was more doofus than flim flam man. He's a good actor most of the time but this just wasn't right for him.
It was campy but not in a good way. Like the sign for China Town, which would lead one to a town made of actual china (like plates, teapots, cups, etc.).
They stole a bit of story from Three Amigos. Ok, I'm sure Three Amigos stole this particular bit of story from many other movies but I can excuse it because Three Amigos is an awesome movie.
The acting from most of the main cast was, um, not great. I've seen these people do so much better so it was frustrating to watch them struggle with what I think should have been more campy and less serious. Of the three witches I think Rachel Weisz did the best with the material but that's still not saying much. Mila Kunis needed to relax a bit and Michelle Williams should have gone with a more cutesy approach (she got close but held back).
There's more but I just don't feel like getting into it. It doesn't help that I saw the movie with the most annoying audience filled with yapping 5-year old girls, men texting and a large man audibly sucking the popcorn out of his teeth. But I stand by my final consensus. It was more bad than good but only by a little. If it's your kind of thing and you're less nitpicky than I am, go see it on a big screen.