My biggest problem with Wreck It Ralph and it's staying power is like the other Pixar movies, its based in modern day. In fact I think that is the fatal flaw with Pixar movies and the prime reason they don't fit in the Disney parks. None of them take you away to lands of the past, but are rather altered realms of the reality that we live in today. I don't think Wreck-It Ralph will be remembered in 10 years but thats just my opinion.
However, no one, and literally no one knows if it will actually stay around.