Thanks for looking at this, Eddy1.
I can get into UBUNTU using a live CD, yes, as well as edit any of the boot elements. Os-prober returns this:
/dev/sda1:Microsoft Windows XP Professional:Windows:chain
The first update-grub didn't run, but I followed the suggestions and created a /boot/grub file and then update-grub ran and wrote a menu.lst.
I'm realizing though, after having to think it through more closely because of having someone else look at it, that the big problem is probably that I'm trying to use a non installed live cd to try to fix the problem my attempt at actually installing Linux caused. The live cd will almost always reference the temporary files in the system it creates, not the ones resident on the hard drive. Your reply has been invaluable in getting me out of the frustration and exhaustion of the last two days and actually seeing this.
My next step will be to try to do an actual install using any of the four Linuxes I have install disks for and seeing whether any of them gets around this. Right now, if I can just boot the Windows recovery console, I'll declare victory, get out
and do a real Linux install when I've recovered from this.
This mess all happened because I have a highly irrational affection for IBM Thinkpads. I've installed Debian on at least five destktops, with at least three of those being dual boot Windows installs and by now it goes pretty smoothly. I always just allow Windows to rewrite the MBR. When I finally got the courage to try to install Linux into one of my laptops, though, I didn't want to lose any functionality no matter how trivial. I had read that allowing Windows to rewrite the boot record disables the blue Access key (not that I ever even use it, arrgh!) so tried to write the boot record somewhere other than the first partition.
When that failed, I lost access to my Windows system as well, and in an illustration that one should never go all geek and work on these long past the point of frustration and exhaustion, accidentally formatted and so wiped out the Windows partition. I had had the sense to back up a lot of the data, but not enough to make a recovery disk. The recovery partition is still there and thankfully, Ubuntu allows me full access to all files in it, but I can't get grub to recognize it and can't get rid of grub, not even by reformatting all partitions except the recovery one.
Sorry for the long reply - and thanks again for your very useful (and terse!) suggestions.
Lexia