Super Mario Bros. 1, often merged with Donkey Kong. It's wholly possible to meet people who think they're the same game. And good luck finding anyone who knows that there was a Mario Bros. arcade game before there was SUPER Mario Bros., or that Donkey Kong arcade had not one, but two sequels.
On the topic of Halo; all weapons are from the first game, except for the Battle Rifle, Energy Sword (which are from the second game) and the Gravity Hammer (from the third game). Same thing goes for all the vehicles, except for the Wraith (also from the second game).
Similarly, DDR is the only BEMANI game in the West, due to being the only BEMANI game to see more than a small handful of Western releases, unlike other games such as jubeat and Sound Voltex which are arcade success stories but have only seen very limited releases outside of Asia (an under-the-radar tablet version for the former, limited export runs to specific arcades in the case of the latter).
Rhythm games with plots are usually not on the radar, however if they are referenced it's probably Parappa The Rapper considering how it is.
Sonic the Hedgehog, known among non-gamers only for the classic Mega Drive/Genesis titles, and chances are if a classic Sega game is brought up, you can always expect Sonic the Hedgehog to be mentioned, and a few other significant Sega classics like Golden Axe or Columns if they're really, really on the ball.
Tomb Raider. The only thing that non-gamers know about the game series is that it features a certain very busty heroine.
Doom; in fact, people used to call the First-Person Shooter genre "Doom clones". Mostly because there was a short period after its release where almost every FPS was a Doom clone.note And this is despite the fact that Wolfenstein 3D actually predated the original Doom.
Call of Duty and Modern Warfare. Remember the aforementioned "Doom clones" example? If you're a first-person shooter, let alone a 'modern' or 'near future' shooter, expect to be called out as a Call of Duty clone.
On the topic of Call of Duty itself, there weren't any installments before the fourth game.
Dungeons & Dragons or a Brand X version thereof—Sometimes this is assumed to be the title of a video game, by people who have heard the name and have no idea that tabletop roleplaying games exist.
Real-time strategy games in general probably don't exist, but if one does, it is almost certain to be Warcraft, especially since its MMO spinoff became such a huge success.
Pitfall. Few non-gamers might know the game's name, but the basic image of a stick figure-like man swinging on vines over lakes and pits seems to be rather familiar to people in general.
If you're lucky enough to find a work that references a fighting game, it's Street Fighter or Tekken. Otherwise it's a generic anime-styled combo-fest. Mortal Kombat, too, if people remember that it's a fighting game and not a gore simulator.
As for the Street Fighter, all characters from Street Fighter II. Of the original eight, five have penetrated mainstream pop culture (Ryu, Ken, Chun-li, Guile, and Zangief). Blanka, Dhalsim, and E. Honda aren't so lucky. While all the original bosses are well-known, only Cammy of The New Challengers is widely recognized. And last but not least, Akuma of Turbo. Of the Alpha sub-series, only Sakura and Dan are known by all.
As for Tekken, it's a little better since Tekken 3 is widely considered to be the best of the series and introduced a plethora of new characters including series protagonist Jin Kazama, so there's more characters that can be referenced. Also, the Updated Re-release of Tekken 5 introduced Lili, who quickly became one of the most popular characters in the series. Anything else however will go over most people's heads.
Fighting games with fanservice? Obviously Dead or Alive. That is, assuming people remember that it is indeed a fighting game and not a Jiggle Physics simulator. Also, there are no males characters in the series (except for Ryu Hayabusa, by virtue of being the star of the well-known Ninja Gaiden series). The Soul Series is also starting to head in this direction for its increasingly infamous fanservice.
Ace Attorney. Phoenix Wright is the only protagonist of the series, in fact they're often called the "Phoenix Wright games". Also, don't expect a non-fan to be able to tell you anything else about the series besides the Objection!meme.
Darkstalkers. The only thing people can remember about that game is the Morrigan Aensland, the sexysuccubus who has appeared in more Capcom Versus Whatever games than her own. The only other characters people might remember are Lilith (by virtue of being Morrigan's moe sister) and Felicia (who is a near-naked cute monster cat girl). Good luck finding a non-fan who can name another character, or can remember that the actual protagonist of the series is Demitri Maximoff. As you can tell, Darkstalkers is Best Known for the Fanservice, and almost nothing else.
"All video games are violent/inappropriate and are therefore a bad influence. Therefore, they must be subject to more regulation than movies/TV/music/books/the internet." Unfortunately, because politics are involved with this one (and because it's a long story anyway), we'll need to leave it at that. And remember kids, if a game promotes religion it should get an immediate E-rating. Violent video games promoting Judaism/Christianity/Islam/Buddhism... don't exist.
The only reputable PC game distribution platform is Steam. DLsite? Playism? GOG.com? What are those? If a PC game has been released, but it's not on Steam (yet), as far as the general public is concerned it doesn't have a release at all.
Because of the female Wii Fit trainer's memorable reveal for Super Smash Bros. for 3DS and Wii U, many people forget that the game also had a male trainer. Despite the fact that he was an alternate costume for her in the series, it has still yet to fully reverse these perceptions.