Oh ... best robot in a movie by far!
Until yesterday I would have said Robby The Robot from "Forbidden Planet" or the Bubble-headed Booby from "Lost In Space" were the coolest movie robots, but yesterday I say this movie "Settlers".
Steve was his name - and what a great design. I think if you check this YouTube video maybe you'll agree - Steve blows the other robots away, and seems like he could almost be real.
Steve - the Robot from "Settlers"
https://www.youtube.com/watch?v=OSj_a9TvExk