Mivas: But do you remember characters other than two or three persons from the main quest? Do you recall some of their unique lines? Their character's traits? Does solving some quest provides character's growth (not you)?
Specific lines? No, I remember a single specific line from any game ever, and I tend to get even that one wrong unless I google it.
Specific characters? I don't remember their names for the same reason why I don't remember the lines, but for characters themselves, from the main storyline alone, I remember 5 - that's the Morrowind's storyline alone, not counting the expansion. As for side quests and stuff like that, I do remember a couple as well, including their specific characterisation. Admittedly, even that isn't that great, except for like 3 or so (not counting daedra lords here, their their own chapter entirely)
There's something else I remember tho, and I only recall a single other game where I would remember such a thing and find it as intriguing, and that is politics. Every organization, every leader, had their own motivations, goals and background, and if you are perceptive, you can actually follow their actions and figure out their repercussions. Even the main storyline wasn't as simple as "Go and kill the evil guy", as much as it leads you to believe so - the events that led to the game's current situation were fairly complex, and when I took my time and researched the backgroud (which is, of course, avalible directly in-game), I felt half-compelled to turn at the 'good guys' (which you actually can do and if you kill them, game offers you a back door to finish the main storyline regardless. Pretty cool.) And the best part is, the reason why you are led to believe that you're going to kill the bad guy is a result of long and thought-trough manipulation and deception.
My biggest gripe with the modern TES games is that they took a lot of that complexity away. Well at least Skyrim tried to do it again, just not quite as well.