Superman Returns had a good Superman but a boring script and was just really dull. Routh could have been great, but Singer was obviously not the person to make a Superman movie.
Superman II: The Richard Donner Cut is the best of the Christopher Reeve Superman movies, even if its ending is weird because of how Superman I & II were messed with as they were being made.
Man of Steel is literally "What is a nutty Ayn Rand fanboy made a Superman film", and its exactly as crap as you'd expect with that idea behind it. It looks bad, the story is bad, and the main character may be called Clark Kent but he sure as hell isn't Superman. Its still better then the next movie on the list, though.
Batman v Superman Its crap, and was originally hilariously long crap until it got cut down to overly long crap.
Justice League is not great, but its ok and I actually believed Cavill was Superman in it, since we got an injection of actual humanity and heroism into Superman. As a movie its better then Superman Returns, but even though I warmed up to Cavill a bit in this I still count Routh as the best modern live action Superman.