For Planets, it would probably be Venus because something could live in it's atmosphere, but it would be a lot more likely have to be between Titan or Enceladus (moons of Saturn or Europa (one of Jupiter's moons). Enceladus really is interesting though because it has water, which is the key ingredient to support life. So if humans move to Mars and there isn't enough water, then go to Enceladus.
Mars.
MARS.
MARS.
Earth.
So far the answer is Earth... But we are still looking around...
Mars.
MARS.
MARS.
Earth.
Mars
Yes venus has just been discovered to have micro organism's living 50km above the crust. Yes, venus is most likely to support life.
So far the answer is Earth... But we are still looking around...
Earth is the most habitable planet in the solar system, which is why there is so much life on it. As far as we know, no other planet has life on it. Mars could possibly support human life, with supports to help them.
It would have to be Io, Titan, and Europa. These are moons though, not planets.
Mars
Mars and Venus
Possibly, but the new planet will not have any life forms. (Most likely.)