I've played all Elder Scrolls games, the main series and spin offs (minus the phone games). Of those the only ones I haven't beaten yet are Battlespire and Oblivion. Now as for if Skyrim will be better than any of them. I'm not sure as I haven't played it yet. IMO, the less of an rpg it might be than is predecessors, the worse it is. My favorite was a tie between Daggerfall and Morrowind, though I voted Daggerfall due to its options available to the player.