Do you prefer to follow one quest line all the way through or just do whatever quests come your way in whatever location you happen to be? I've found that concentrating on following a quest line to completion gives a better feel for the story behind it. If I do a bit of this quest and a bit of that tend to forget conversations and lose the narative.

Same here. Once I start some longer quest I don't tend to follow other quests in the middle, or I lose track of what exactly I was doing, or rather, I lose the "mood".

I used to always stick to one quest at a time otherwise I would end up completely losing the plot and have no idea what my character was supposed to be doing.

I have major OCD so I'll stick to one until it's complete.

I do tend to start quests for specific goals (like becoming a member of a group) and then letting things hang. There are many times when become the Archmage or Harbinger simply clashes with the PC personality whereas being in the organization is not an issue.

I just do what ever the character feels like doing or feels is best for the character.

it depends. I often do not complete the guild quest lines, but join just for the radiant quests and pick up side quests while doing those.

When I do the main quest, I do not run straight through the quest without taking the side quests from the greybeards or the Blades to get get more shouts and unlock them. I don't like rushing through the main quest.