cant restore my iphone !!!!!!!!!

i cant restore my iphone .... ihave tried both the way i mean the normal restoring where itunes downloads the software and DFU where i downloaded a firmware but nothing is working ....

when i tried reseting my iphone through reset option from the phone itself .. a white screen appears with a apple logo and a progress bar ... it completes 80% after that a black screen comeup with a process circle whiich countineously rotating but do not show any result ....

help i am stuck !!!