Non System disk or Disk Error

Ok i am having a bit of a time with this one, i have 2 HP NX6110 notebooks i am working on for a client, 1 with a clearly fried MoBo, and one with a bad hardrive. The one with a bad harddrive i went into the bios and ran a HDD check from the bios and i get read error, i try it in another laptop, same thing... ok bad HDD. Then i take the HDD from the notebook with a bad MoBo and stick it in the other laptop, this time in the bios, the option to run a HDD check is greyed out, so i set the boot order to USB drive > CD rom > HDD and i stick a xp install disc in.... it waits then "Non System Disc or disc Error" so i try a vista disc, same result, Ubuntu 8.10? Same result. I know all these disc work i have used them before... So i try a LiveUSB ubuntu and a LiveUSB XP same thing... Any suggestions?