Namco was one of the first out of the gate with what we now see as the modern retro compilation. The Namco Museum series dates all the way back to the original PlayStation. It continues today with games like Namco Museum DS, which collects a handful of arcade games, slaps them onto a DS cartridge, and ships them out to stores. It's a fairly straightforward compilation with some interesting options and features.
Right off the bat, you're given a cool intro sequence that cleverly combines the graphics from all of the Namco classics. Then you're dropped off into a menu where you've got seven arcade games to choose from: Pac-Man, Galaxian, Galaga, Mappy, Xevious, Dig Dug II, and The Tower of Druaga. These all appear to be emulated versions of the original games and run on the top screen of the DS. The bottom screen is devoted to options. You can rotate the view and play vertically by holding the DS sideways, which makes the games fill up the whole screen without stretching them too much. If you want to play horizontally, the graphics get squished in weird ways and generally looks pretty bad. For example, text is practically unreadable on the default settings. You can also make adjustments to the game's difficulty and go to a "hardcore options" mode, which shows you a picture of an arcade circuit board, complete with the tiny little switches that were used to make those adjustments on the real machine. It's not a major feature, but it's a neat inclusion. The games all play just like the arcade originals, which means that Dig Dug II and The Tower of Druaga still aren't a whole lot of fun. But it also means that Galaga, Mappy, Xevious, and Pac-Man are still just fine.
In addition to playing the classics, there's a version of Pac-Man Vs. on the cartridge. This was a multiplayer version of Pac-Man originally released on the GameCube. The multiplayer ghosts vs. Pac-Man gameplay has been well duplicated on the DS, and you only need one copy of the cart to play it, which is nice. You'll also find a library section with some historical info about each game and a sound test mode where you can listen to all the music, as well as sound effects, from each arcade game.
Of course, all of this is meaningless if you aren't already interested in new releases of old games. And if you are, there's a fairly good chance that you have at least some of these games in other formats. With that in mind, there's nothing too special about this package that makes it stand out from the pack, save for its portability. If you're in need of an arcade-quality Xevious on the road, this will do the trick.