GRUB error '21' problem

[tom]

hi list,

i am having problems getting GRUB to work (dule booting win2K and redhat 8
on 2 different HD's) and i could really do with some pointers  =)

at first (after a default instalition) i was getting a HD Error but i have
modified my grub.conf

here is a list of my partitions:

drive /dev/hda
           dev/hda1   NTFS (win2K)

drive /dev/hdb
           dev/hdb1  ext3 /boot
           dev/hdb2  ext3 /usr
           dev/hdb3  ext3 /home

        /dev/hdb4    'extended'
           dev/hdb5  ext3 /
           dev/hdb6  swap
           dev/hdb7  ext3 /var

and this is my grub.conf file:

// --- grub.conf

# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE: You have a /boot partition. This means that
# all kernel and initrd paths are relative to /boot/, eg.
# root (hd1,0)
# kernel /vmlinuz-version ro root=/dev/hdb5
# initrd /initrd-version.img
#boot=/dev/hda
default=1
timeout=10
splashimage=(hd1,0)/grub/splash.xpm.gz
title Red Hat Linux (2.4.18-14)
    root (hd1,0)
    kernel /vmlinuz-2.4.18-14 ro root=LABEL=/1
    initrd /initrd-2.4.18-14.img
title Windows 2K
    rootnoverify (hd0,0)
    chainloader +1

// --- end grub.conf

now on boot up i am getting this output:

    GRUB Loading stage1.5.


    GRUB loading, please wait...
    Error 21

both win2K and redhat 8 are woking (if i fix the MBR it will boot to Win2K
normaly and i get to redhat with a boot disc)

if there is any other information i need to post please ask... i am failry
new to linux and lists btw

thanks in advance

tom