The whole movie has such an air of giddy adventure that I had a good time with it. Journey 2: The Mysterious Island is charming, in spite of its imperfections.
The only defense for this movie is to say that it's not actually 'trying' to be good ... Are we supposed to applaud just because they set the bar low and barely reached it?
The equivalent of those pre-made sandwiches you buy at Starbucks -- not bad for you, and not entirely lacking in flavor, but nothing particularly memorable, either.