Skyrim is the best Elder Scrolls game and is better than Morrowind in every way possible, from world design, to combat, to lore, everything. I played Morrowind, and was bored to absolute tears, the only thing I like about the game was the rather odd aesthetics that gave the game a sort of ethereal feel, which I wish more games did...but besides that I cannot in good conscience say that I understand fans fervor over Morrowind.
Half Life 2 is nothing special. This may be because I didn't play it upon release and I didn't get a chance to see what all the praise was about until much later, but I was rather disappointed. It was just a regular old shooter...story was kind of interesting but it didn't hold my attention.
Dark Souls in how it presents it's story is perfect the way it is and should not change in it's sequels. I know this opinion in unpopular cause I see tons of people complain about it. The story is presented through item descriptions and character dialogue, leaving the player..you...to fill in the gaps making the game somewhat of a mystery game, depending on how you play it. The sense of discovery lends itself well to the overall design, as it adds to that rewarding feeling when you either beat a boss or realizing the vague connection from one part of the story to another.
Bioshock is the best FPS game ever made and was so much better than System Shock. I played both, and found Bioshock's narrative substantially better, but it's gameplay and atmosphere was far superior to that of anything System Shock had to offer.
Diablo II was a terrible, repetitive, and ultimately boring game. Diablo III was much better, everything felt smoother and more natural in the grand scheme of things.
Errr...that's all I can think of for now.