Can anyone help me out , the quickpwn is asking me for bootloaders and I haven't got a clue what this is. Please Help !!!

What are bootloaders ? I am stuck on this page on the quickpwn.

Hello everyone, I'm a new jack here, and I have a simple question. First let me set up the question. I bought this iphone off of someone on the street. the phone seems to be powering properly, and the guy said everything is restored to new. the phone is a 8gb 3g AT&T. I went to itunes and it asked me to activate the phone with at&t, which is my courier alreaady. My question is will there be some kind of trouble if I activate with at&t, being as though I purchased the phone off of the street. What I'm basically saying is that the phone could be stolen or something like that. The price was to good to let the phone go , that's why I bought it. Hope you guy's understand. Sorry for taking up so much of your time. Thanks in advanced..