I think Daggerfall was the superior game in terms of mechanics.
Reasons:
In Daggerfall you could contract vampirism and lycanthropy (werewolfitis). I caught both at some point, and the city guards would just go flying like ninepins, hand-to-hand was just epic stuff. Plate armour would just crumple like foil. And when you know the full moon is drawing near, and your pulse starts to quicken...And skulking around by day as a vampire lends a whole new aspect....of course, you could join a vampire guild but first you would have to find one, and be accepted by them.
In Daggerfall, dungeons were created on the fly so there was no possibility of messing up later quests. In Morrowind, if you raid the wrong dungeon and sell the wrong piece of kit, you can screw up progression in a guild. In Daggerfall, every dungeon is new and it could take days to clear one out fully.
In Daggerfall, you would arrange to meet people at a certain tavern on a certain date, say three months later - miss the appointment and miss a strand.
In Daggerfall, you could buy a horse and ride it around, you could buy a house in every town if you had the money, you could buy a boat, etc.
In Daggerfall, if you knew the right date and right location you could find any number of witches' covens and go out to the countryside to bust in on their special ritual nights. Of course, the dates and locations were very difficult to find out, and they were tough fights, but still worth it in terms of prizes.
Daggerfall is easily the most open-ended game I've played, if they had just redone it instead of making Morrowind it would have easily been the best RPG ever without question. Maybe it still is though, just not easily.
