Hurrah! I have the password! The software I used works! I had to run it on a desktop machine because it had a gruntier serial port. Of course the laptop does not boot because I removed the hard drive and CD-ROM, but once I desolder the wires to the EEPROM and reassemble it everything should be well...
Thanks for the encouragement on and off list. I think another laptop must be purchased, but at least I will be able to continue using the old one for a while longer, and it gives me time to research before I buy. The final installment of this saga will be broadcast right here on this list. The planned programme includes a gleeful statement of how everything is working after reassembly[*], and a glib recap of how cool it is that my mum is using Linux. Andrew -- [*] Subject to change without notice.
