I recently bought a used laptop that had xp home already installed, everything seemed to be running fine but I wanted to do a clean install of XP

When I went to install the system the dvd drive seem to stopped reading during install and the setup stopped completely and now the bios will not recognise that there is a dvd or cdrom drive installed at all. I have fitted another dvd drive all lights are on and you can hear the drive spinning as tho it were reading the disc but still the bios does not see this drive.

The bios does recognise other usb drives when fitted and the hard drive as well, any ideas of how to rectify this problem will be appreciated, thankyou

Also when I try to install system from the USb drive it comes up with an error NTldr not found???

Go back into the BIOS. Set the drive detect to auto or try load defaults.