In no particular order:
Silent Hill 2 Played this game with my friend. The first one was good, but the improved graphics, controls, and just overall scariness, put it over the top. The little things like trying to open a locked door, walking away, and hearing the knob rattle from the other side... Terrifying. Also, Pyramid Head didn't hurt the fear factor at all.
Final Fantasy VIII I grew up with this game. I love it to death. Favourite Final Fantasy game of all time. I loved the story, the characters (screw you, Squall
did have character development, although he did change a little abruptly at the end of Disc 3), and the Junction mechanic, while allowing an easy low-level playthrough, served me well once I got the hang of it. I love this game despite its faults.
God of War 3 I was never a big GoW fan (never played the first two

) but I decided to give this one a shot. I don't believe I have ever experienced 10 hours of such polished, cinematic gameplay before this game (save for maybe Uncharted 2). The sheer scale and epic-ness of this game is incredible, and the boss deaths are brutal and just plain awesome. Just when I think Kratos can't possibly kill somebody in a more extravagant fashion, he does. Amazing.
Honourable Mentions Uncharted 2: Among Thieves (I really wanted to put this on the list, but I had to fit FFVIII on there for the nostalgia), Black Ops (say what you want about the campaign, I thought it was the best of all the CoD games), Bioshock (this probably would have made it on the list if I didn't already know the big twist before playing it).
Also, keep in mind, I've just started Metal Gear Solid 4 today (I know, I'm late), so the standings may change, you never know.