Sounds like there's a corrupt file on the install DVD (or one that is corrupting whilst copying to the hard drive) which is causing the install to fail. Currently you've only got a partial OS installed on your computer, which is why it won't boot into Windows (starting a clean install has deleted the system files for your old install).
I assume you did a full system image backup before you nuked your old install? No?
If the install disk is corrupted (although this is unlikely) you'll need to pick up a new install disk from somewhere (or buy a copy of Windows 7!). It might also be worth downloading a copy of parted magic, which is a live Linux disk that contains lots of tools for managing hard drives including methods for erasing all data. This would mean you essentially had a "fresh" disk to start the install on, which might help. I've had similar problems with Windows XP installs that were down to the sata mode hard drives were working in too, but that shouldn't be a problem with Vista...