You can't simply convert a fat32 partition into ext3. Either hda10 or hda11 are probably already ext3.
The boot strap loader is written to the MBR in the first 240 bytes of the disk. This will load the next stage of the grub loader which is probably located in /boot/grub/ on one of your linux partitions.
I inserted RHEL 4's 1st CD and then linux rescue...
then chroot /mnt/sysimage
Before chroot'ing, look at what is in /mnt/sysimage. Make sure that this is your root partition. Check if the /boot directory contains the kernel and root directory. If not, you may need to mount the boot partition under /mnt/sysimage/boot.
After chrooting, I will run "bash -l" to run root's .profile & .bashrc scripts. This will set up the paths.
Then try mounting /proc.
proc /proc proc defaults 0 0
I think that fedora has a command to repopulate the devices in your new /dev directory but I don't remember what it is. You could copy the files from /dev/* to /mnt/sysimage/dev/ before chrooting.
I don't have RHEL so I don't know if you are using LVM. Perhaps the rescue disk created the Logical volume for you and mounted it under /mnt/sysimage/.