Think WarioWare Gold, except there's no extra controls. Every game uses the A/B buttons, including the DS ones that were touch-screen specific. There are some new stuff and extras to unlock, but you'll be pulling your hair out trying to 100% the game due to a pachinko game that gets VERY FRUSTRATING near the later levels.
Also each game has a gold star that you need to acquire. How you do this is that a star hole will be shown at the bottom of the screen and when a certain part of the song comes up (and for each song, the sections are always different and can be at the very beginning, or very end of the song), and then an outline of the star starts to close in on the hole. You have to get perfect timing on that part once the outline touches the hole of the star in order to get the gold star. If you're off by like a milisecond, it doesn't count.