For the record: Could get into X by selecting 'recovery' at the grub prompt, and then logging in at the black screen, and then using startx. However X still had the wrong resolution - something dodgy about the whole thing. So just gave up on Ubuntu and installed Debian, it seems to have a new stable version, Squeeze?? The problem with upgrading to Ubunto ?11.4 *might* be that I had forgotten that the security hardening program Bastille was installed:
to remove it.
Huge thanks, unfortunately did not spot your post before putting in Debian. Incidentally get impression it is possible the 'Module' is something to do with the login program and perhaps not X.