Kernel panic/invalid node structure; please help retrieving my files!!

Hi everyone, thank you for your time in advance... if anyone has ideas about how to solve it, I appreciate this very much!

OK, here is how it began: while I was working on the airplane using PowerPoint, the gray spinning wheel appeared after which PowerPoint stopped working. I pressed the power button to exit (all applications froze). (So much for trying to get more work done...)

Next, I powered up the computer but it would not boot up, with only gray spinning wheel showing.

Next, tried to boot up while pressing power button and holding shift key. After some time (10 minutes), an error message appears. Researching it on discussion forums, I found that it is called “kernel panic”. Here is beginning of the message:

panic(cpu 1 caller 0x47f5ad): "Process 1 exec of /sbin/launchd failed, errno 8\n"@SourceCache/xnu/xnu-1504.15.3/bsd/kern/kern_exec.c:3145

Debugger called: <panic>

[additional information here]

Also, message “You need to restart your computer. Hold down the Power button until it turns off, then press the Power button again” is shown transparently in the middle of the screen over the “panic” message output.

I turned on and off the Power button many times, but I get the same error message.

I also tried Apple Hardware Test but it did not work (it did not generate any messages).

Next, I tried to use the Disk Utility using the Installation Disk that came with the computer. After I clicked “Disk Repair”, here is the log:

Verify and Repair volume “Macintosh HD”

Checking Journaled HFS Plus volume.

Checking extents overflow file.

Checking catalog file.

Invalid node structure

Rebuilding catalog B-tree.

Invalid node structure

[many repeats of “Invalid node structure” ~ about 400 repeats]

Rechecking volume.

Checking Journaled JFS Plus volume.

Checking extents overflow file.

Checking catalog file.

Missing thread record (id=18)

Missing thread record (id=110)

[many instances of “Missing thread record” ~about 200 repeats]

Checking multi-linked files.

Checking catalog hierarchy.

Checking extended attributes file.

The volume Macintosh HD could not be verified completely.

Error: Disk Utility can’t repair this disk…disk, and restore your back-up files.

At the end, a window presented over the error log stated :

“Disk Utility stopped repairing “Macintosh HD”

Disk Utility can’t repair this disk. Back up as many of your files as possible, reformat the disk, and restore your back-up files.

I need to retrieve my recent files!! Please Help!! Argh!! I promise that I will promptly back up my files now! I did not use Time Machine, and only some of my files are backed up.

From what I read on the discussion forum, I will probably need to erase the disk and then do a fresh installation, but could someone please guide me with regard to how to back up the data / retrieve the files? I may have access to another mac so I’m thinking that the FireWire Target Disk Mode may work. I also have spare external harddrive (formatted for mac) (not partitioned). Also, how do I retrieve the files from the other computer if the FireWire transfer works?

Also, the second step is to do a new installation, but is there any reason why “Archive and Install” using Disk Utility won’t help? I have some additional programs installed (Illustrator, Photoshop) so this means if I do a new installation, I will need to re-install those as well?

I did some investigation, and it looks like this problem is similar to this:

https://discussions.apple.com/thread/3862376?answerId=18098343022#18098343022

But my main issue now is to retrieve the files!

Also, how do I investigate whether this problem is due to a failing hard drive or a natural file system corruption ? (so should I get a new harddrive or do a new install).

http://forums.macnn.com/t/459376/heart-attack-invalid-node-structure

I don’t know what is the OS version; it is Snow Leopard OS X ……. I bought it in September 2009.

I appreciate any help, thank you so much for your time…