A curious thing, whilst getting my desktop computer ready for reformat where I opened the case and gave it a good de-fluff and replaced the thermal paste on the CPU to heatsink assembly, I flipped the CMOS battery out and left it out for a while... what I usually do when I am in there.
Anyway on starting the computer I discovered something, well three things really, the grub menu of which never worked was working and I could access the Windows side as well as the two linux distros I have on the machine ( Petra Cinnamon and Rebecca XFCE). The other thing I discovered was despite my boot order being set to CD-ROM first, the CD-ROM doesn't start up and so the computer loads from the HDD of which is not what I was wanting. ( Mind I have been having problems with the DVD drive of late, same problem as I am experiencing now, but sometimes it ' catches ' and works, but not all the time, so I have been leaving the desktop on all the time)
The third thing I discovered was my original problem was still apparent, Rebecca XFCE was not recognising my password, of which is the same password for the installed distro I am online with now, (Petra) so something has gone wrong with Rebecca.
So, Bios, given what got fixed by wiping the bios memory by battery removal, can there be a problem with the bios ?
And Rebecca, the not recognising password issue, what's going on there ?
And finally the DVD drive, it not starting despite boot order, is it shot ?