My DH and my song is: "When You Say Nothing at All" by Keith Whitley. Been married 6 years and we will still start playing the song just for the chance to dance to it.
I don't think I've ever slowdanced with my SO. As for romance... well, the only card he's ever bought me was some horribly mushy thing and inside he wrote "You make my insides all runny... or maybe that's from the Olestra"...