Thanks for the suggestions djohnston. I should explain, I am dual booting the laptop with Win7 and PCLinuxOS, but want to do a clean install of PCLOS, hence downloaded MiniMe.
I am puzzled, as the computer reads the disc perfectly when running my current install of PCLOS. I pop it in the drive, and can mount, read all files, copy the CD, whatever, so there doesn't seem to be a problem with physically reading it. As yet, I have never had a problem with this optical drive reading anything once the computer is up and running. But several versions of linux have the same booting problem. I don't worry about the others because I just try them to keep up to date with what they're doing, but PCLOS is what I use every day, so I want to be able to do a clean install if I need to.
Anyway, have found a workaround. On the desktop I used the utility in MiniMe to make a bootable USB stick. Same iso file, same CD, running live on the desktop. The USB stick version boots perfectly on the laptop, and this is what I will use next week for the fresh install.
It's a puzzling one, and I wonder how many others may be having the same problem.
Regards, and thanks again.