I remember playing DDR Extreme in the arcade and being pleased as punch at the prospect of a US port coming to me on the PS2. Then I got it and while the song selection is wonderful, the interface nearly ruined the experience for me. After playing DDR for a bit, you're conditioned to certain aspects of the game. Mainly, the options and the small graph changed. In fact, there wasn't a graph there. However, that's not really problematic. If you're not an obsessive player like me but know enough about the franchise to appreciate Japanese songs then I highly recommend you seek out a copy to complete your collection.
My little one liked it and she is 12, but she also has the new game that just came out with the pad. I did ask if she liked the game and she said it was ok and she felt it was more like a 5= fair, I think with this game being old that's why she picked 5.