Well, I'd want to get together with the crew and to all brainstorm and vote on one together.
I'd probably like to name it after a heroic member who died or something getting there or setting up the colony. Or, since it's habitable, make contact with any native intelligent life and find out what their name for it is.
Failing those two, I'd perhaps name it after what it looked like from space (Marble, Blue, etc), or a conspicuous feature of the planet (Twomoon, etc.), or perhaps I'd just name it Home or Haven or Newlife or something like that.