For swing dancing, look for the Royal Swing Ball on the DL schedule. The schedule/calendar should list the band playing for a particular night (there are different bands each Saturday). Dancing starts at 7:30pm-ish (sometimes we are allowed in a bit early) and ends promptly at 11pm. The dance floor on Dapper Day Saturday tends to be more crowded than usual, so keep that in mind if that might be a problem. If you have any more questions about the swing dancing at DL, please ask!
Oh, and sometimes there is dancing in DtD. The DLR calendar should list bands and locations. If the band is rockabilly, there will probably be some dancers in the audience! When Tomorrowland Terrace has Scot Bruce or Hard Days Night, the swing dancers had over there, too. And there is swing dancing in DCA in Paradise Gardens (by Goofy's Sky School), when the Ellis Island Boys play.