PC:
Age of Empires 2, and all of its expansions.
StarCraft , played this a lot. For me it was a tie, which I enjoyed more. I didn't care fore the Zerg though.
Battlefield 1942, includes Secret Weapons of WW2. I played this a lot. I remember playing online, the lag was so bad, plus I was a newb.
Battlefield Vietnam, was fun. I remember my dad commented on the soundtrack.
Since my new laptop will play SC2 I will probably get it. I have it installed(need to pay for a copy), playing only the intro is horrible. I will have to config it for offline play only :?
Console, this will be long.
N64
Goldeneye007, Perfect Dark. Loved these two immensely, wished my emulators could work good for them.
PS2
Didn't own this one very long.We got a dud system, started failing after the warranty went up
Nightfire, plus a few others. my younger brother used this console a bit.
Midnight Club, my first racing game
Gamecube - Never owned one. It retrospective I wish I did. I loved Metroid :/
X-Box
Nothing else mattered for me.
H.A.L.O 1&2 !!!! Need I say more
Goldeneye Rogue Agent, I remember the campaign being harder than I expected. Multiplayer was fun though.
X-Box360
Halo 3!!!!
Perfect Dark the original version. Loved that paid feature.
Project Gotham Racing 2, lots of fun
Forza series, Even more fun.
Then we sold it.