Question

1.

Answer 1

1. I believe it this, they way the question is phrased it seems like a personal opinion. But if we're being logical about this, no one likes background noise. So,yes, it's important. 
2. Yes, when you record something you don't want additional sound that has nothing to do with what you're recording. 
3.Yes, your main task is to be focused on what you're doing on the computer. You don't want to be distracted by unnecessary distractions.