I have played I through IV, and not a Dragon Quest higher. Out of those four, I seemed to enjoy DQIV the most—even though I only got as far as Chapter IV.

The different characters every chapter were probably what I enjoyed most about it. I really liked playing as Taloon; during the early stages of the chapter, I would disappear into the fields for days slaying monsters. Then, reeking of the foul remnants of slaughtered wild beasts, I would return to my wife, where we would fight (and make up afterwards). I had to use my imagination for that part, though not very much (stomp, stomp; shuffle, shuffle). After the love making was done, I would return to the wilderness and the clock was at 12 again.
Taloon was also so cute! Most surprised I: didn’t suffer sun damage.