Even without all the voice acting, fancy graphics, humor and story, Portal 1 and 2 is one of the best puzzle game/series hands down.
The portal concept is one of the best game play innovations to come around lately. I'd go bananas over a futuristic themed FPS that incorporated this concept, and I don't usually play FPS.
Now add all the voice acting, etc... and it's clearly hovering around the top. And it has an excellent, simple control scheme.
ive played Portal on my 3D dual stack projection system and its pretty cool especially on a large 3D screen but not #1. driving games and FPS games are the most popular and my favorites. need to try some flight sims.