Using the live disk, went back to the old (failing!) 80gig disk, edited back to where I was, bound the /dev and chroot and mounted what I needed. update-initramfs and lilo worked without any segfault.
So back up. Time to buy another big disk and move stuff or reinstall with Jesse. Trouble is these big SATAs are not so great. That 80gig IDE which smart claims is pre-failure (but does not totally support) predates them all.
