Sometimes, I really don't feel like Dance Dance Revolution is an actual video game. Since it normally requires you to exercise, I feel like it breaks the rules, but in a very good way.
Playing DDR, I lost a lot of weight and found tons of music that I really love, so I'd recommend it to anyone. I've taught kids how to play too because I think it's just that much of a worthwhile game. You can technically play it with your controller, but I found the timing to be strange and that takes the real fun of the game out of it!
The newer games in the series are adding a bunch of extra options, but my favorite is the combo challenge. Basically, in that mode, if you miss a single step, it's game over, but it's fun to see how many you can get in a row. At my best, I think I got around 1,100 steps.
And the really good news is that two of the DDR classics (Extreme and Max 2) have been reprinted at a cheaper price, so you shouldn't have to dig hard to find them at all. :D