Just a thought... it could be your optical drive since you are getting different errors on different disks.
I thought that at first, so i had a look at if there were any drivers i could use and also checked that the optical drive was showing up in the Bios..... I found no drivers but i came across a tutorial to install vista/xp using a usb memory pen.... which actually solved the problem but gave me problems further on... i also thought that there may be problems with the hard drive but i did a few checks and that seems fine..