Digimon World
Bomberman 64
Chrono Cross
Final Fantasy IX
Majora's Mask
Ocarina of Time
Panzer Dragoon
The Capcom fighting games on Saturn (Vampire Savior, Marvel vs Street Fighter etc)
Albert Odyssey
Tales of Eternia
I could go on and on. I loved the vivid sprites, prerendered BGs and early 3D creativity of the 5th gen.
Shadow of the Colossus
Ratchet and Clank PS2 trilogy
Resident Evil 4
Resident Evil code veronica
Hi Fi Rush
World of Warcraft
Diablo 2
Tales of Symphonia
I could blabber on but to answer your title I would say Digimon World is the most beautiful game I have played. I love it's unique CGI art style.