Grub won't boot

[S. Gordon von Miller]

Hello,

Ubuntu reloads once after installation and refuses subsequently to
boot.  I installed Libranet on another drive, and
Grub didn't find Ubuntu even though its on another drive.
So I inserted the following in menu.lst. Ubuntu is /dev/hb1 on the
second drive.

  I get an error message.

root (hd1,1)
Filesystem type unknown, partition type 0xf
Kernel /boot/vmlinuz-2.681-3-386
root = /dev/hdb1 ro single
Error 17: cannot mount selected partition.


This is how it is in menu.lst.  What  is wrong with it.

title           Ubuntu, kernel 2.6.8.1-3-386 (recovery mode)
root (hd1,1)
kernel /boot/vmlinuz-2.6.8.1-3-386 root=/dev/hdb1 ro single
initrd /boot/initrd.img-2.6.8.1-3-386
savedefault
boot

Thanks.

Gordon