My iPhone 2g wont restor I try dfu mode nothing happen

there could be a few reasons. the first reason is your not putting it in duf mode but are letting go of the buttons to soon. hold down the power and home button for at least 12 sec then let go of the power button and keep holding the home button. do all of this wile your phone is connected to the pc and itunes is running and I can guarantee that it will work 99% of the time. this might take you a few tries but ill work. (iPod screen does nothing when put in duf mode)

hope this helps