Ubuntu :: Use LiveCD To Access Filesystem

I'm using Ubuntu 8.04 LTS in a dual boot environment with XP. Except that I have two hard drives: One with Ubuntu and XP and one with just XP. The MBR on the XP-only drive has an entry named "Linux" which points to the grub loader for the split drive. I tried to reinstall windows on its partition on the split drive, but the install process hung and I've never figured out how to make it finish. I didn't use that partition for this entire episode. Yesterday I booted into Ubuntu and tried to log in, but immediately after entering username and password I was presented with an error message (full screen, blue background, red "ok" button). I don't remember exactly what the wordage was but it had something to do with a hard drive error.

I thought I was experiencing hard drive failure, but I hit the reset button and successfully booted into the windows-only installation. I didn't think the problem was anything more than a random error. Today I tried to boot into Ubuntu, but immediately after the splash screen I was greeted with BusyBox v1..1..3 with an (initramfs) prompt. I restarted and tried Ubuntu again and immediately I encountered the grub> prompt (no grub bootloader, no splash screen). Confused about why the prompts had changed I decided to boot into Windows, but at the welcome screen an error dialog from lsass.exe informed me of an unrecoverable error in the registry: the semi-famous "registry could not read in, write out, or flush." Next I tried the live CD.

Using the live CD I could access the contents of both of my windows partitions, but not my Ubuntu partition. Navigating to "FileSystem" using the LiveCD only yields the directories created for the LiveCD session. I tried again to boot into windows and it worked, so I'm hoping the message from lsass.exe was just a random hiccup. Right now I'm pretty much only concerned with getting the Ubuntu partition backed up, and then performing a fresh install. Content from the windows installations is fully backed up. The fact that using a LiveCD gives me access to the windows partition on the split drive makes me certain that the drive has not physically died.

Using "fdisk -l" produces no output, and "dmesg" gives some errors at the end of the output:
[310.832172] EXT3-fs: unable to read superblock
[341.900881] VFS: Can't find ext3 filesystem on dev sda5.
[887.351098] end_request: I/O error, dev fd0, sector 0
[899.495785] end_request: I/O error, dev fd0, sector 0
[899.495795] Buffer I/O error on device fd0, logical block 0
[911.636348] end_request: I/O error, dev fd0, sector 0
[911.636359] Buffer I/O error on device fd0, logical block 0
[1032.849498] end_request: I/O error, dev fd0, sector 0
[1044.999986] end_request: I/O error, dev fd0, sector 0
[1044.999996] Buffer I/O error on device fd0, logical block 0
[1057.130682] end_request: I/O error, dev fd0, sector 0
[1057.130693] Buffer I/O error on device fd0, logical block 0
[1146.185858] attempt to access beyond end of device
[1146.185872] sda2: rw=0, want=4, limit=2
[1146.185878] EXT3-fs: unable to read superblock
My attempts to use the grub> prompt to reinstall grub return an error (error 15, I think?) when I try "find /boot/grub/stage1".