How to restore an iphone 3g?

Please help
my brother in law was kind enough to give me an iphone 3G as my phone is broke, only problem is he said it needs rebooting because its in shock mode? How do i do that?
the phone won't turn on all i have is a blank screen, i plugged a charger in and it said on my itunes page to enter a passcode but i can't as its a blank screen, i have my own itunes account for my ipod so will it recognise this iphone as its registered in my bro's name?
the battery is fine as far as i'm aware i just want to restore it to factory settings and treat it as new, how with a blank screen? Any help will be appreciated
theirs a switch on the side of the phone when i switch it it vibrates? Good or bad? I'm new to the iphone world

You should be able to see it pop up on iTunes. When in iTunes go to the 'Devices' tab on the left hand side, a screen will appear showing your phone, then under the sub screen 'Version' there should be a 'restore' button, click that! See how you go.

You can also restore your iPhone by recovery mode press power and home botton till it show like connect your device to itune and connect to iTunes, it say restore than click restore.