[ifyouwantto]

Not dance it, though. Personally I’d only have a prayer of identifying it because I’d recognize it as “not Flamenco… probably?” and that’s nearly the end of old-timey dances that I know the names of, so I’d guess waltz. Not because I actually know what it is, though—you could probably trip me up by picking any of several other kinds of non-waltz dances to show me, and I’d call them waltzes too.

[tanewishly]

It depends where you're coming from. The waltz has a very different rhythm to most other music. If you can tell (obvious) waltz music from (obvious) non-waltz music, you could identify the dance fairly easily. But if you do not know the musical difference between a waltz and a tango/foxtrot/jive/etc, then you'd need to know specifics of the dance to tell them apart - and could be fooled, eg. by pairs in ball costumes doing a different dance.