Why i can't to repair the Grub Error 15?

Question

Hi.
Unfortunely, Arch Linux don't work for me.
I tried to fix the Grub Error 15, without success.
I have two hard disks, one installed in /dev/sda (with Ubuntu)
the other in /dev/sdb and it is where I want to install Arch.
As I do not want complications, simply i assigned /dev/sdb1 to "/" and /dev/sdb5 to swap. /home /boot /etc and other directories are in the same partition as /.
The kernel are in the /boot directory, the files are /boot/vmlinuz26 and /boot/initrd.img (i don't remember the exact name of this last .img file)
My menu.lst are as following
default 0
timeout 3
title        Arch Linux
root        (hd1,0)
kernel    /boot/vmlinuz26 root=/dev/sdb1 ro
initrd        /boot/initrd26.img
However, always shows me the Grub Error 15 (File not found).
I enter to the Grub command line
grub > root (hd1,0)
Filesystem is ext3, partition type 0x83
grub > setup (hd1)
Checking if '/boot/grub/stage1' exists... yes
Other checkings (I don't remember which now) also passed and exists (they say "Checking if 'file' exists..... yes").
But when I boot from the second hard disk, the boot fails and the damn grub error 15 appears.
Nothing and none of the tutorials that I found in Google works.
What i'm doing bad?
Thanks!
EDIT:
Here is a summary of check with efsck, to discard failures on the disk, however, had many attempts with error when reading certain blocks like this
Error reading block 2163066 (Attempt to read block from filesystem resulted in short read) when getting the next node -i to examine 
¿Ignore error? Yes
¿Force rewrite? Yes
Summary:
36215 inodes used (0.76%)
38 non-contiguous inodes (0.1%)
# of inodes with ind/dind/tind blocks: 1173/8/0
471916 blocks used (2.48%)
0 bad blocks
1 large file
30943 regular files
3551 directories
3 character device files
0 block device files
0 fifos
1469 links
1709 symbolic links (1709 fast symbolic links)
0 sockets
37675 files
Last edited by El-Dani (2009-02-21 03:49:55)

Answer 1

I typed these commands in grub command line
root (hd1,0)
setup (hd0)
... and then?
I not understand why appears the same error. Mi menu lst is here
title  Arch Linux
root   (hd1,0)
kernel /boot/vmlinuz26 root=/dev/sdb1 ro
initrd /boot/kernel26.img
vmlinux26 and kernel26.img exists in /boot directory. I want to boot from first partition of second hard disk, which are sdb1.
Are there other way to boot Arch? (which is installed in the second hard disk, in sdb1)... maybe editing the grub using to boot Ubuntu? (Ubuntu is installed in sda1)
Is valid simply adding the lines of my menu.lst described above and paste it in menu.lst of Ubuntu?
I boot Ubuntu normally from first disk, first partition. Here is the menu.lst of the disk installed with Ubuntu
title        Ubuntu 8.04.2, kernel 2.6.24-16-generic
root        (hd0,0)
kernel    /boot/vmlinuz-2.6.24-16-generic root=UUID=5b72d0b0-af94-4e37-ba6b-13008ce75e31 ro quiet splash
initrd        /boot/initrd.img-2.6.24-16-generic
As you can see, Ubuntu is in the partition /dev/sda1 (hd0,0). Can I simply adding the arch lines to this menu.lst, and boot from first disk as normally i do? I want to select booting Ubuntu or Arch.