ok im not iphone king but i kinda no my way round them

bought faulty needin a screen and a battery, not knowing what firmware or anything

bought the lot stuck them all in

went to restore an update using itunes to 5.1.1
but once it gets to veryifing restore with apple
but the phone keeps restarting to the apple logo an keeps restarting

i've tried ireb an nothing
tried everything i no off but i really am stuck

can you guys help?