Hi there I've downloaded FC3 via bittorent and burn all 5 disks, using these disk I upgraded my laptop from FC2 to FC3 with no problems. When I try to upgrade desktops with the same disks they fail, I have then tried a media check of the disks and they fail, so I've burn more disks only to have them fail. How does one go about checking the downloaded iso images are sound before burning a bunch of coasters? TIA