That being said, Daggerfall and Morrowind had more sandbox elements to them. More depth and choices. More of the feel that you really didn't need to do anything unless you decided it's what you wanted to do.
Oblivion is kinda the oddball one to me. It had half the graphics of Skyrim, the broken feel of the combat from Morrowind (un Modded), weird half realized NPC AI, and (to me) a kind of cliche plot.
If Daggerfall or Morrowind had Skyrim's graphics and a slick combat feel (not the whole system, just the smoothness and ease) that Skyrim has, they would be better hands down. In fact, give Daggerfall Morrowind's graphics and Daggerfall becomes the hands down winner. I'd pay serious cash if Bethesda took Daggerfall and replicated it using the new graphics engine. Even limit the scope of radiant AI to just regions around important towns etc and it could be done.
Skyrim is a great game and is worlds ahead of any recent product on the market. It's probably going to be the best new game we'll see for a while. But it lacks the WHALEFIST punch of opportunities and options of Daggerfall and Morrowind.
Maybe the Modding community will fill in those gaps.

