My pick is 1991-2000. That includes the fourth, fifth, and beginning of the sixth generations - in my mind the top three generations.
We saw amazing games from Nintendo, Sega, Capcom, Konami, Rare, Square, Valve, Namco, LucasArts, and Blizzard. Some of the industry's best games arrived during this stretch, including A Link to the Past, Super Metroid, Final Fantasy VI, Super Mario 64, Final Fantasy VII, GoldenEye, Banjo-Kazooie, StarCraft, Half-Life, Ocarina of Time, Panzer Dragoon, Shining Force, Metal Gear Solid, SoulCalibur, and Deus Ex. There was so much experimentation, competition, and innovation. Truly a golden age.