[lug] grub2 boot (ubuntu 10.04)

[Davide Del Vento]

I have just installed Ubuntu 10.04 on a machine. Now, it refuses to
boot by itself, it stops at the grub> prompt.
If I type
	
linux /vmlinuz root=/dev/sda1 ro
initrd /initrd.img
boot

It boots fine and everything works. However I need this machine
booting by itself, I cannot be there in person at each reboot. I tried
to modify /etc/default/grub according to the stuff I manually type,
without any success (in particular, I changed the
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" to either "ro" or
"root=/dev/sda1 ro" and I also tried to uncomment
GRUB_DISABLE_LINUX_UUID="true" since it's an old laptop). No way, it's
a lonely machine which wants company of an human being.

Suggestions?
Thanks a lot
Davide

PS: I'm getting crazy, now that I was becoming familiar with grub and
its menu.lsf, they come out with this crappy grub2. GRRRR I want LILO
back (I'm ok with putting the kernel at the beginning of the disk,
what else was wrong with it?) - I know, I still could do it, but then
it'll break the automatic updates of the kernel, so that's not an
option.