The Quest for Glory series. If I absolutely had to narrow it down to just one though, it\'d be QFG2. Engrossing atmosphere, awesome storyline, clever puzzles, cool monsters, and the absolute best ending of the series. It\'s graphics and interface however.. well.. most people don\'t like em. Personally, I prefer the Text parser to the cursor because it draws you more into the game.. and I can overlook the fact that it\'s in 16 color EGA. (Although it\'s an absolute MASTERPIECE of EGA art.)
The one feature about it that I most like is the ability to save off your character and import him into the next game of the series rather than starting fresh from scratch every time. I wish more games would let you do that.