This is fairly common. From Googling about it, apparently it only happens if Vista is installed after a previous operating system such as XP or Linux on this hard disk.
I would try wiping the disk clean so it looks like a brand new hard disk. Just a format is not sufficient because it doesn't remove what is in track 0 (the MBR boot code and the partition table).
I recommend you download Seatools for DOS using another PC and install it onto a bootable CD.
Seagate Technology - SeaTools
It comes as an iso image file. Don't just copy it onto the CD like you would with a music file, use the CD burner's option for "burn CD from iso image file".
If you don't have a CD burner such as Nero you can use the freeware ImgBurn
The Official ImgBurn Website
Seatools has several hard disk tests and also an item on its menu for wiping the hard disk (which overwrites every byte with zero).
Boot the Seatools CD on the problem PC. First run its tests to be sure the disk is not faulty. The surface scan test will also lock out any bad sectors from being used. Then do a 5 minute wipe with zeros. There's also an item for wiping the entire disk which takes a very long time but the 5 minute wipe is sufficient to clear track 0 and the first few tracks of the first partition, which is all you need.
Then when you start the Vista installer it will see a brand new HD so it will offer to create a new partition, format it as NTFS and install Windows on it.

Originally Posted by
Vista Dan
To hell with the company. Ask for a refund. Trust another dealer.
This problem can happen with a genuine Vista DVD. I doubt if it's the fault of the company he bought it from.