If you are fed up of stock DDR, but not dance games, look into finding the PS2 version of In The Groove [http://en.wikipedia.org/wiki/In_the_Groove_(game)]. Basically DDR redone by a different company, and improved to the point where it started earning triple what DDR machines did in the arcades (when placed in the same spot). New modes, new modifiers, new steptypes (rolls and mines), you HAVE to use hands for some songs, and the highest difficulty is a 13.
Or you can find the PC version, which has more songs, and get a converter for your pad. PC converter also allows you to play Stepmania [http://www.stepmania.com/]. Never gets old as you can upload any song you want into it assuming someone made the stepchart for it. Oh and its open source so completely free.
Non-dance games that may and have worked include pretty much every 2D platformer that doesnt rely on analogue controls or sholder buttons. I have also had some good fun playing some racing games on my pad.