Thanks Rich, you temporarily dispelled my fears. But it crashed again today. I only switched it on to update my iPod touch. As soon as the sync-update/transfers ended with the beep in the normal way (if you are familiar with the Apple devices you will understand) the computer went blank unexpectedly. I rebooted successfully without a warning that it had not "shutdown properly" so was not prompted to select "safe mode" this time. That was odd.
I did look at the "Event Viewer" this time and I could see an immense Administrative list of warnings and errors but what is a layman to make of all that. Looks quite ominous to me.
If you have read this far I thank you. Racing off to the nearest electronics store to get an external hard drive before I loose the lot.
Kind regards,
Grechan