These scores are highly subjective! I’m not trying to be an objective reviewer here: all of these scores are heavily based on my experience (and probably also influenced quite a bit by nostalgia). Your opinion may vary wildly.

Each score is an overall score of how much I would recommend this game to someone who has never played it before. This doesn’t necessarily mean it was or wasn’t a groundbreaking or famous game, or that its graphics/sound/music/etc. were great/crap, but that the overall experience was good enough that I hope you’ll check it out, or bad enough that I’d say “don’t bother.” Also, I’m grading somewhat on a curve, which means that B- or so is average, not bad; and that B+ or so is pretty good, not just average. Or, in other words:

• F: Don’t bother. This game sucks and you suck if you like it.
• D-/D: Not really recommended for anyone.
• D+/C-: I didn’t like it much, but you may.
• C/C+: Eh, it’s OK. Play it if you’re bored.
• B-: This game is average. I’d play it every so often, but I probably wouldn’t seek it out.
• B: Above average. This game probably made it into my regular Atari-playing rotation.
• B+: Very good. You will most likely enjoy this quite a bit.
• A-: Excellent! A top tier game.
• A: Games that make it here are the cream of the crop. If you haven’t played this game yet, stop reading and go get it!
• A+: These are games I still play today, even though my main Atari-playing days are behind me. Everything — the graphics, sound, music, controls, gameplay, replayability factor — all comes together perfectly, resulting in nothing less than the most stellar game possible.

For more info see this post from which the above blurb was mostly copied (though it uses the outdated number system).

A+

• Ballblaster (aka Ballblazer beta)
• M.U.L.E.
• Pitfall II

A

• Bruce Lee
• Lode Runner
• Necromancer
• Rescue Mission (aka Rescue on Fractalus beta)

A-

• Blue Max
• Claim Jumper
• Cosmic Tunnels
• Donkey Kong
• Donkey Kong Junior
• Encounter
• H.E.R.O.
• Joust
• Jumpman Junior
• The Last Starfighter (aka Star Raiders II beta)
• Miner 2049er
• Pharaoh’s Curse
• Star Raiders
• Super Cobra

B+

• Drelbs (also a video)
• Gorf
• Fort Apocalypse
• Frogger 2
• Hard Hat Mack
• Mario Bros.
• Mr. Robot and his Robot Factory
• Ms. Pacman
• Picnic Paranoia
• Pogoman
• Pole Position
• Popeye
• Preppie
• Serpentine
• Track and Field: Los Angeles 1984 Summer Games

B

• BC’s Quest for Tires (also a video)
• Congo Bongo
• Gamestar Baseball
• Kangaroo
• Missile Command
• Monster Smash
• One on One: Dr. J vs. Larry Bird
• Pacific Coast Highway
• Pharaoh’s Pyramid
• Protector II
• Qix
• Quarxon
• Race in Space
• Wizard of Wor

B-

• Amphibian
• Berzerk
• Centipede
• Clowns & Balloons
• Defender
• Fast Eddie
• Galaxian
• Java Jim
• Kaboom!
• Mouse (Mouskattack)
• Pinhead
• PitStop
• Star Wars
• Tumble Bugs

C+

• Asteroids
• Dog Daze
• Kid Grid
• Nautilus
• Pacman
• Salmon Run
• Slime
• Snake Byte
• Speedway Blast
• Survivor

C

• Baja Bug
• Caverns of Mars II
• Dig Dug
• Embargo
• King Tut’s Tomb
• Shooting Arcade
• Submarine Commander
• Turmoil
• Vanguard
• Wayout

C-

• Knockout!
• Onslaught
• Pool
• Professor I.Q.
• Super Breakout

D+

• Atari Invaders
• Buck Rogers: Planet of Zoom
• Canyon Climber II
• Firebird

D

• Crossfire
• Froggie
• Reversi

D-

• Flying Ace
• Journey to the Planets
• Stargate Courier
• Starion
• Zaxxon

F

• Apple Panic
• Jumbo Jet Pilot
• Monster Maze
• Night Mission Pinball
• Starbowl Football

Unrated

• Eastern Front 1941
• L.E.A.P. Disks 1-4 and 5-9
• Jeff’s BASIC Games