Frequent kernel panics-Who can decypher/help?

So, cut to the chase. I've read a bit about the Invalid Sibling Link. Some say run variants of FSCK in single user mode, some say put startup disk on Spotlight's privacy list, then re-add it. Here's the question: Is there a good, known way to fix the Invalid Sibling Link thing, or should I proceed to a clean (re)install?

Interesting that AHT found the RAM problem, where running Rember all night didn't. Don't want to be gloomy, and hope the new RAM is the fix, but just bear in mind that it might be the RAM bay, not the RAM stick itself that's giving you a hard time. You'll find out when you try the new RAM stick in that bay. As to the Sibling link error, having done abundant research you probably know more than I about what's available. But just in case you haven't come across this one, and in case you don't want to lay down the money to buy Disk Warrior:

http://hints.macworld.com/article.php?story=20070204093925888 Remember to first unmount, then remount the drive according to the directions. And, of course, this will depend on being able to boot to the install DVD.

Since you may not be able to boot to the DVD, you can certainly try--and keep repeating until it says it's fixed--fsck in single user.

http://support.apple.com/en-us/HT203176

Scroll down to Use fsck if necessary.

Also, if you have a totally trustworthy bootable clone-backup, you could reformat the drive and then move the clone back. But don't try that unless you have that clone.

Read again. So you do have a backup and you are able to boot to the install disc. You may have mentioned this before, but what kind of backup?

Well, if you can't fix the directory error any other way, and don't want to spend a lot of $ for Disk Warrior, which is basically recovery software (and no guarantee it will be the fix), you could reformat the drive, then install Snow from scratch, then bring over all your backed up stuff and reinstall any third party applications (it doesn't look like you have a lot (Firefox, etc.). If you do this, be sure to use Software Update to get anything you need current, and as soon as you reinstall Snow apply the 10.6.8 Combo Update. Also, be sure to update again to the latest Flash player. A clone would be nicer, but this is what you've got.

http://support.apple.com/kb/DL1399

To do a reformat, open Disk Utility>select the drive (the top level listing, which will include the name of the manufacturer)>Partition tab>select 1 partition (if that's how it's currently set up) and hit Apply. Make sure it's set to GUID partition scheme, MacOSExtended (Journaled).

Just wondering, why clone? Could it also bring back possible directory problems that may've led to the KP's or "cannot be repaired" issues?

Not directory problems, as Carbon Copy Cloner and SuperDuper (the most commonly mentioned clone utilities) are file and attribute copies. Directories and file metadata is created new on the destination drive. Attributes are applied after that. File data is copied into new files. Directory entries are created as files are created (again all new).

Kernel Panics will either be existing hardware which didn't go anywhere, or are from software which would indeed be copied as part of the clone.

Back to the recursive fsck thing, I suppose to re-mount the disk afterwards, I just look for the Mount button at the top of **? What if I'm in Terminal or single-user (ie, command line) interface, do I just type " mount /dev/disk0s2 " to reverse the un-mount? That's the part the instruction in the link you sent forgot to mention. And if, for some reason, it will not mount again (as some commenters reported), I suppose I still have the option to do a clean install?

Quite simple to do that. http://osxdaily.com/2013/05/13/mount-unmount-drives-from-the-command-line-in-mac -os-x/

I would also run diskutil list first in Terminal to be sure you have the correct volume, rather than relying on the instructions in the MacWorld link.

>>I think I'm gonna re-install.

Remember that's a reformat and reinstall. An ordinary reinstall of Snow would preserve everything, but not this. The reformat will do a total erase, so you must be prepared to redo everything, Mail, network and regular settings, third party apps, photos, music (iTunes library), etc., the whole lot.

Glad we're on the same page, but no need to have done a secure erase (zeros). Only needed, for example, if you're selling or giving away the computer.

One more thing. Don't know if it will make a difference for what you need to do for getting the directory straightened out, but you probably want to do a reformat, not an erase. Won't take all that long.

That's good. That was the easy part, now the real fun begins.