Above all:
Deus Ex: The blend of stealth, action, RPG, FPS, player choices and story made it the best SP game ever made imo. I must have played it through about 8 times and found something new on nearly every play through.
The rest:
Metal Gear Solid 1: Absolutely amazing and revolutionary for its time
Super Mario World: Quite simply the perfect 2D platformer
Metal Gear Solid 3: The story was truly captivating in this iteration
Final Fantasy VII: A classic, with a superb cyberpunk world and story
DragonAge: Origins: Ambitious and brilliant RPG.
Zelda: Link's Awakening: Yes, my fave Zelda was on the Game Boy because it was just perfect in every way :P
Half-Life 2: The perfect SP FPS.
Oblivion: Awesome open world RPG, with an improved battle system over Morrowind. The mods really make it though.








