I thought the answer was obvious but apparently some don't understand or haven't played Guitar Hero.
Guitar Hero is exactly the kind of game that appeals both to casuals and to hardcore gamers. If you play it at low difficulty it is perfect for casual gamers, on the other other hand if you invest time the game gets really skill based and it definitely takes lots of play and practice to master the game at the higher difficulties.
Also, Guitar Hero is a game because you have a series of objectives and scores and the main focus of the game is beating content to advance and unlock more content as you would in other games but instead of levels you got songs.
Wii Fit the main objective is fitness not progress in the game, there is score keeping and such in some of the Wii Fit 'games' but it's not the objective of playing it. There is no gaming skill or improvement envolved but rather improvement in fitness and exercise and yoga or whatever...
Add on top of that, that guitar hero while having a guitar shaped peripheral, is still really a game where you press buttons to try and defeat objectives as in traditional games, even if it is the case that the contoller is not in the normal shape.
Did you ever consider rythm games not to be games before? No. Do you consider EBA not a game simply because it is you tapping to music? no.
Wii Sports is a game, not a traditonal game, but it is a game because the objective most of the time is to defeat your oponent. Wii Fit is a collection of fitness routines and very few things that could possibly pass as games (like the soccer game).
On the other hand, DDR is a game just not a video game. That is a dancing game, the software and machine is only there to keep score of your movements and 'dancing' and isn't essential to the experience but adds to it.
Thanks to Blacksaber for the sig!
