A point that people often take for granted is the idea that "proving" the ressurection establishes the truth of Christianity. It does not. The claim that "Jesus rose from the dead" and the claim that "faith in Jesus provides forgiveness of sins" are different claims and need to be verified independently. It is the latter claim that is vital to Christianity being true (even if Jesus' resurrection was only 'spiritual', the second claim could still be true). It seems to me, however, that this second claim is much harder to establish.