Kernel Panic!

[Kent Frazier]

Hello all.  I am not quite sure what's going on with my system, but
after shutting it down last night and rebooting this morning, I was
greeted with the following friendly message:

pivot_root: No such file or directory
/sbin/init: 431: cannot open dev/console: No such file
Kernel panic: Attempted to kill init.

I am running the latest Hoary with the k7 2.6.9 kernel.  I still have
2.6.8 and 2.6.7 installed, and I tried them all (normal boot and
recovery) but got the same message.  With the normal boot, the message
came after "Starting Ubuntu...".  With recovery, it came after "NTFS
driver 2.1.14 [Flags: R/O MODULE]."

I decided to run Memtest, to see if that was the problem, and I found
over a hundred errors in RAM.  So, I thought, that is the issue, time
to order new RAM.  I was able to boot into a Knoppix CD just fine,
however.  Since Knoppix was running, I thought it still may be an
issue with Ubuntu.  Inside Knoppix, I chrooted into my Ubuntu install
and did an "apt-get update" & "apt-get dist-upgrade".  Then I
rebooted.  The kernel panic was still there, but had changed a bit. 
Now it said:

pivot_root: No such file or directory
/sbin/init: 428: cannot open dev/console: No such file
Kernel panic - not syncing: Attempted to kill init.

Thinking it was likely still the RAM, I pulled 256MB of RAM from an
older system and stuck it in this one and ran Memtest.  No errors on
this RAM.  Rebooted and the kernel panic was still there.  So I
rebooted into Knoppix, and now here I sit, trying to figure out how to
fix my ailing system.  I searched around a bit, and found that
apparently some Mac users were getting a very similar message after
install.

A bit more backstory, just in case it is relavent.  Previously, I had
my Ubuntu install all on one 20 GB partition, while Windows occupied
one of my hard drives completely and took up the rest of the space on
the Ubuntu one.  I decided I wanted Linux to have more space, so I
backed up and then wiped out the 200GB HD and reformatted it into 2
ext3 partitions.  I tried to do a fresh install from recent  Hoary CD
images, but neither Array 2 nor the Daily would run X afterward, and I
couldn't figure out how to fix the issue, so I decided to move the
current install.  I booted into Knoppix and copied everything from the
old root over to the new empty 20 GB partition with "cp -ax".  Then I
copied my home directory over to the new large partition and deleted
it from the new root.  I edited fstab and added the new home.  Then I
rebooted, and everything worked quite well (I had installed grub on
the new HD during the botched Hoary installs, just had to edit
menu.lst a little.)  This is the first problem I have had since, so I
don't think this caused the problem, but I thought I should mention
it.

Is anyone experiencing anything similar?  Does anyone know how I can
fix my beloved Ubuntu?  Is this related to a recent dist-upgrade (one
day I'll learn to stop blindly doing those)?

Thanks in advance for any help.

Kent