There are ardent purists out there who will think that anything past NES is not retro, but lets face facts the XBOX first gen is now officially 18 years old. So how long is long enough for something to be considered vintage or retro?
Besides I think if it's a good enough game people are willing to budge on their comfort levels.
Retro vs. "vintage" is actually a good debate to have.
If I were to posit definitions, "retro" is anything 10+ years old.
What was once "retro gaming" should really be called "vintage gaming". The "early days" of retro gaming were defined by Atari VCS, NES, SNES, and Genesis. What you could call the "golden age" of video games before everything was distilled into just a handful of genres and graphics were what mattered most.
As for stuff work playing;
VCS (2600 for newfags):
-Yar's Revenge
-Pacman Jr.
-E.T. (If you actually read the manual)
-Porn games/Texas Chainsaw Massacre/Halloween (due to the novelty/uniqueness of those titles)
-Mario Bros.
-Popeye
-Donkey Kong
-Jungle Hunt
-Kaboom
NES:
-Mario Bros.
-Super Mario Bros.
-Super Mario Bros. 2
-Super Mario Bros. 3
-Metroid
-Kirby's Adventure
-Gauntlet II
-Wizards and Warriors
-Wizards and Warriors II
-Anticipation
-Spiritual Warfare
-Narc
-Wario's Woods
-Tengen Tetris
-Alien Syndrome
-Ducktales
-Mega Man
-Mega Man II
-Mega Man III thru VI
-Punch-Out
-Ninja Turtles
-Ninja Turtles II: The Arcade Game
-Micro Machines
-Holy Diver
-Castlevania
-Castlevania III: Dracula's Curse
-Battletoads
-1943
-New Ghostbusters II
-Little Samson
-Mr. Gimmick
-River City Ransom
-Batman
-Adventures of Lolo
-M.C. Kids
-Blaster Master
-The Immortal (Pre-Cursor to Diablo)
-Smash T.V.
-Captain Skyhawk
-Snake, Rattle, and Role
-Contra
-Dr. Mario
-Krazy Kreatures
-Rad Racer
-Double Dragon
-Double Dragon II
-Dragon Warrior
-Final Fantasy
-Zelda
-Zelda 2
-Ninja Gaiden
-Ninja Gaiden 2
-Ninja Gaiden 3
Master System:
-Golden Axe Warrior
-Safari Hunt
-Choplifter
-Master of Darkness
-Rastan
Genesis:
-Sonic the Hedgehog
-Sonic the Hedgehog 2
-Sonic the Hedgehog 3
-Sonic and Knuckles
-Sonic 3D Blast
-Dr. Robotnik's Mean Bean Machine
-Altered Beast
-Chakan the Forever Man
-Robocop vs. Terminator
-Splatterhouse 2
-Splatterhouse 3
-Dinos for Hire
-Mutant Football League
-Mutant Hockey League
-Super Baseball 2020
-Skeleton Krew
-Madden 93
-NBA Jam: Tournament Edition
-Streets of Rage
-Streets of Rage 2
-Streets of Rage 3
-Golden Axe
-Golden Axe 2
-Mortal Kombat 3
-Street Fighter 2 Champion Edition
-All of the Disney Games
-Haunting: Starring Polterguy
-Earthworm Jim
-Earthworm Jim 2
-Earthworm Jim 3
-Lethal Enforcers
-Ninja Turtles: The Hyperstone Heist
Super Nintendo:
-Super Mario World
-Super Mario World 2
-Earthbound
-Super Metroid
-Street Fighter 2 Turbo
-Donkey Kong Country
-Chrono Trigger
-Final Fantasy 3
-Mortal Kombat 2
-Kirby's Dream Land 3
-Starfox
-F-Zero
-Mega Man X
-Mega Man X2
-Mega Man X3
-Doom
-Spider-Man and Venom: Separation Anxiety
-Blackthorne
-Demon's Crest
-Robocop vs. Terminator
-Simcity
-Mario Paint
-Battletoads and Double Dragon
-Battletoads in Battlemaniacs
-Boogerman: A Pick and Flick Adventure
-Super Castlevania 4
-Clayfighter: Tournament Edition
-Judge Dredd
-Killer Instinct
-Link to the Past
-Sunset Riders
-Lethal Enforcers
-Liberty or Death
-Super Bomberman
-Super Mario RPG
-Ninja Turtles Tournament Fighter
-Turtles in Time
-Mario's Picross
-Ninja Gaiden Trilogy
-Super Gameboy (Technically a peripheral, but you can do some stuff with it by itself. Also, see the next list)
Gameboy/Gameboy Color:
-Super Mario Land
-Super Mario Land 2
-Super Mario Land 3
-Donkey Kong Land
-Donkey Kong Land 2
-Donkey Kong Land 3
-Donkey Kong Country
-Pokemon Red/Blue/Yellow
-Pokemon Gold/Silver/Crystal
-Pokemon Trading Card Game
-Link's Awakening: DX
-Kirby's Dream Land
-Kirby's Dream Land 2
-Kirby Pinball
-Gameboy Camera
-Street Fighter 2 (But only if playing on Super Gameboy)
-Space Invaders
-Adventures of Lolo
-Avenging Spirit
-Trip World
-Battletoads
-Battletoads in Ragnarok's World
-Faceball 2000
-Mario's Picross
-Mega Man 2 thru 6
-Mega Man: Dr. Wily's Revenge
-Tetris
-Rolan's Curse 2
-Pac Man
-Ninja Turtles: Fall of the Foot Clan
-Ninja Turtles 2
-Ninja Turtles 3
-Spiritual Warfare
-Battletanx
-Cannon Fodder
-Conker's Pocket Tales
-Zelda: Oracle of Ages
-Zelda: Oracle of Seasons
-Perfect Dark
-Resident Evil Gaiden
-Super Mario Bros. Deluxe
-Wario Land 2
-Ghostbusters 2
-Wario Land 3
-Final Fantasy Legend
-Spud's Adventure
-Final Fantasy Legend 2
That's it for vintage console games. Can't give a list of 5" or 3.5" PC games as I don't know much about that stuff. But if guys want some more Retro stuff that isn't "vintage";
N64:
-Super Mario 64
-Ocarina of Time
-Majora's Mask
-Battletanx
-Pokemon Stadium/Stadium 2
-Pokemon Puzzle League
-Shadows of the Empire
-Rogue Squadron
-Spider-Man
-Donkey Kong 64
-Mario Kart 64
-Perfect Dark
-Golden Eye
-Mario Party 2
-Nightmare Creatures
-Yoshi's Story
-Kirby and the Crystal Shards
-Bomberman Hero
-Resident Evil 2
-Doom 64
-NFL Blitz
-Star Wars Pod Racer
-Super Smash Bros.
-Gauntlet Legend
-Diddy Kong Racing
-Conker's Bad Fur Day
PSX:
-Final Fantasy VII
-Final Fantasy VIII
-Diablo
-Castlevania: Symphony of the Night
-Dino Crisis
-Dino Crisis 2
-ReBoot
-Resident Evil
-Resident Evil 2
-Resident Evil 3
-Nightmare Creatures
-Nightmare Creatures 2
-Final Fantasy Tactics
-Crash Bandicoot
-Whatever was the final Madden
-Whatever was the final NHL
-Whatever was the final MLB
-Twisted Metal
-Twisted Metal 2
-Grand Turismo Series
-Road Rash
-Grand Theft Auto
-Metal Gear Series
-Phantom Menace
-Legacy of Kaine
-Soul Reaver
-Mega Man X4
Gamecube:
-Godzilla Fighting Games
-Rogue Squadron 2
-Gun
-Wario World
-Super Smash Bros. Melee
-Hunter: The Reckoning
-Eternal Darkness
-Judge Dredd: Dredd vs. Death
-Gauntlet Legend: Dark Legacy
-Gameboy Player (To play Gameboy Advance Games)
Gameboy Advance:
-Anything in the NES Classics line
-Super Mario Advance
-Super Mario Advance 2
-Super Mario Advance 3
-Snood
-Advance Wars
-Link to the Past
-Zelda Games
-Monopoly
-Pokemon Games
-Warioware Games
-Sonic Advance
-Altered Beast: Guardian of the Realms
PS2:
-Final Fantasy IX
-Final Fantasy X 2
-Ghostbusters
-Resident Evil: Outbreak
-Resident Evil: Outbreak File #2
-Resident Evil 4
-Legacy of Kain: Defiance
-State of Emergency
-Judge Dredd: Dredd vs. Death
-Narc
-Urban Chaos: Riot Response
-Mega Man X Collection
-Dragon Ball Z Games
-Taiko Drum Master
-Time Crisis Series
-Drakenguard
-Godzilla Fighting Games
-Sonic Mega Collection Plus
-Vice City
-San Andreas
-Ghosthunter
-The last NFL game
-The last NHL game
-The last MLB game
-The last NBA game
-Gun
-RLH: Run Like Hell
Xbox:
-HALO series
-Godzilla Fighting Games
My vintage gaming lists are pretty exhaustive. Lists for other retro systems less so as I am less familiar with those modern systems.