Connecting problems.

[G-baby158]

Hi all, i jailbroke my 2g Iphone it all when well (with quikpwn) and tbh if i'm honest i dont have a clue what you can do with it being jailbroken other than having themes, and i dont really know how to use cyida or installer. Right the problem I have is now when i plug my Iphone into the computer it either crashes my computer or when its connected ok in itunes the internet goes off and i can't get on the internet or connect to my routor untill i have unplugged my Iphone, do anyof you know why this is and how to fix it? I think my fireware is the 2.2.1 (but unsure)