I love science fiction like Dark Side of the Moon, Blade Runner and ANYTHING with Tex Murphy, horror (Jonathan Boakes is the man) and even well done plain ones like the Carol Reed games. Sorry, the best N.D.game I played was Danger by Deception(?)

Hmm, I'm thinking none of the above because to me adventure means exploring a new world. Like Columbus, what will I find there? Genre doesn't even enter into it, not even the story is all that important. It's the wonder of what is to come next that keeps me glued to the computer. That makes inventory important because finding out how it will be used is interesting to me. Helping other characters along the way who then help me in turn is always fun. The background can be anything: fantasy, mystery, sci-fi, with or without touches of comedy.
Horror stuff I try to avoid and as much as I liked Sierra games I never even tried playing Shivers or Phantasmagoria, but on the other hand I did play GK2:The Beast Within and it turned out to be one of my very favorite games, go figure. Actually, I first tried playing Myst and disliked it so much I went back to the store the next day and traded it in for another game (you could do that back then) which turned out to be GK2, my second choice. Well, that cover art didn't inspire any confidence in me that the game would turn out to be so good.

I agree with Paola Croft

Mystery, horror, creepy...with GREAT atmosphere. I have also become spoiled i do enjoy them with great sound, and graphics...OH, and excellent testing!!

Horror all the way! The scarier the better!

Oh, Venus, I totally forgot about Culpa Innata! I agree it fits more than one genre also. I want to add that one to my list as well.

Fantasy, or whatever games like Myst are considered to be.
I like sci-fi if it has fantasy aspects, like Schizm or Sentinel (or possibly Myst/Uru if that's considered sci-fi).
And I like historical games if they are done well.
I don't care much for horror if it's mainly meant to be scary, but I do enjoy supernatural-oriented games if they are well done (e.g. - the Gabriel Knight games and Dark Fall games). I like the mysterious aspect of supernatural games rather than the "scary" aspect.

I like the undiscovered world kind of mystery/journey with some thrills or a sense of wonder. I like them to be smart or help make me feel smart, too. The undiscovered world can be most any genre although, for whatever reason, fantasy doesn't hold the fascination it once did for me. I remember playing RAMA on a commodore 64 in the very early 80's. It was just as much a great experience for me as Grim Fandango or Lost Crown.

The humor games sometimes feel like a greater risk to buy because if it fails to tickle the game becomes an exercise of endurance. Though I will follow Tim Schaeffer anywhere.