Perpetual Emotion - self titled (awesome contra dance tracks but not trad music. If you want Zen trance dancing, this is the one to get. The phrasing is not always obvious, though, so new dancers won't get as many clues as the music of other bands as to the As & Bs. Ed and John made a great pairing)
The Old Sod Band - Grass Roots (our very talented house band in Ottawa. Great trad tunes/arrangements. Still going strong! Calling with them in 2 weeks.) Typically longer tracks of 6-7 minutes
hotpoint String Band - hotpoint Special (different twist on trad)
Giant robot Dance - spontaneous animation (though this seems to be live tracks with the calling muted - longer tracks as a result)
Brittany Bay - spirit of the dance (best choice for spirited trad tunes with terrific, varied arrangements) I bought through their website several years ago. Typically, 3 tunes per medley, 3 times through each tune = 4+1/2 minutes per track, generally.
KGB - Volga Notions (I'll second this choice but check out their other albums as well. Not "driving" but great to dance to with a variety of moods. Many original tunes or original twists on trad tunes)
Elsewhere - find several very danceable tracks on various Lunasa CDs (totally awesome band. but listen through to make sure they don't slip in an extra measure/beat here or there in the tunes you select)
Ken Panton