Hero's Quest (aka Quest for Glory) I got it before they renamed the series. The original PC rpg.
Shadowgate The one on the PC before NES ripped it off.
Evil Islands The game that Dungeon Siege copied. One of the best games ever. The original camera shift, time pausing rpg.
Blade of Darkness (aka Sword of Vengance) What a game should be. The levels should be long (around an hour each) and there should be more than 20 of them. Combat was the best in this game.
Gothic & Gothic 2 Better than Morrowind IMO. Awesome story and believable seamless world.
Halo Nice and long. Great story. Good multiplayer.
FarCry The best of everything. Story, length, beauty, stealth, suspense. Just one of the funnest games I ever played. Try it in Realistic difficulty, that took a while!
GL Quake The dawn of 3D. I payed $300 for a Diamond Monster (3dfx Voodoo1 with 4MB of texture memory) just so I could see 3d in all its accelerated glory!
Ultima Online Freedom! Nothing (yet) has recreated the fun of UO.
Anything and everything that's related to OGRE or the wider graphics field that doesn't fit into the other forums.