Can recover data after 'kernel panic not syncing vfs unable to mount root fs' ?

[userx5]

I need to recover some data of the 'home' directory after kernel panic. Can I achieve that?

I was upgrading ubuntu 11.04, installed (http://www.linuxquestions.org/questions/showthread.php?p=4434687#) on usb.
Failed to upgrade because the main partition had no more space.
I moved one directory of about 100Mb to other partition, but it seemed that in the main partition didn't appear those 100Mb free.
I restarted the computer expecting those 100Mb free.
And kernel panic.

[ 0.789567] Kernel panic - not syncing: VFS: Unable to mount root fs on unknow-block(8,1)
[ 0.789646] Pid: 1, comm: swapper Not tainted 2.6.35-22-generic #33-Ubuntu
[ 0.789716] [<c05c6468>] ? printk+0x2d/0x35


Thank you very much.

[userx5]

I've booted with another ubuntu installed in another usb, and if I mount the first usb which has the ubuntu with the kernel panic problem, on it I just can see directories like 'boot', 'casper', 'dists', 'pool', 'syslinux', and files like 'casper-rw' or 'ldlinux.sys'.

The ubuntu is installed on usb, and my data in the 'home' directory is inside the ubuntu, but because of the kernel panic I can not start the ubuntu. How can I get my data in 'home' directory?

[userx5]

The data can be recovered mounting file 'casper-rw':

> sudo mount casper-rw /media/directory -o loop

Now how can I repair that kernel panic?