I think it's doubtful that a technological civilization capable of interstellar travel would resemble anything we've seen in conventional science fiction. As I pointed out in my earlier post; if we ever do encounter an extraterrestrial civilization, it will more than likely be an encounter between us and their technology rather than an encounter with a biological entity. Even if they could transport a living, breathing, eating, pooping, bag of water and gas across interstellar distances, why would they ever bother coming down here in person and taking all of the unbelievable risks that come with that? More likely they'd do exactly what we do when we need to proxy our presence into a hostile environment or nation: send in an unmanned drone.
As for what sort of life does evolve into technological civilizations on other worlds? Well we have no way of knowing for sure that our "body template" is the only, or even ideal one. But it is certainly possible.