New installation failing to take over from old installation

[Chris Green]

I am trying to install a new Lubuntu 12.10 onto a machine here.  It's a
pretty standard sort of desktop machine with nVidia chipset, intel dual
core processor and two 320Gb SATA disk drives.

The installation seems to work with no problems, I tell it to use the
whole of the 'first' SATA disk for the installation and to install grub
on the MBR.

The result though is that the *old* grub (version 1.99) menu appears
offering me the old version of linux (I think it's an 11.10) and, at the
bottom of the boot list the new version.  If I try and boot the new
version it tells me it can't find the kernel and fails to boot.

How can I do a completely clean install, that's what I want to do?

-- 
Chris Green