2001 is a great year but I like 2004 better:
Metroid Prime 2
Tales of Symphonia
Zelda: 4 Swords Adventures
Metal Gear Solid: Twin Snakes
Final Fantasy Crystal Chronicles
Final Fantasy XI
Metroid Zero Mission
Half-Life 2
Halo 2
Paper Mario: TTYD
GTA: San Andreas
Star Wars Battlefront
Pokemon FireRed/LeafGreen
Pikmin2
Doom 3
Gran Turismo 4
Unreal Tournament 2004
And of course the launch of the Nintendo DS.
https://en.wikipedia.org/wiki/2004_in_video_gaming