We're going to blow up the ship...

Why? This always bothered me since I was 10 and saw it for the first time. Lambert suggests that they get in the shuttle and get the hell out of there. That makes sense to me. Then Ripley jumps in with blowing up the ship. For what purpose? I can understand from a movie point of view. But from a logical point of view, it doesn't make sense if you have already decided to leave. Revenge against the company is probably the only logical thing I can suggest, but is that even worth it? The company already knows about the creature so if the Nostromo makes it to Earth with no crew, I would assume the company would know what happened and take appropriate steps. Mother may even warn the company before its arrival of what happened. Its not like the creature is going to take control of the ship once you leave. My Question is therefore....You are in Ripley's situation, you have decided to leave the ship in the shuttle with Parker and Lambert (assuming that the shuttle takes 3 not 4.) Would you go through all that trouble to blow up the ship and escape risking your life to get down there and back, or would you just get away in the shuttle, allow the Nostromo to continue on its journey and maybe broadcast some signal to warn people about the creature?