Macbook Won't Boot From DVD (boots fine otherwise)

[maxterpiece]

Hello,

I have a white macbook 2.4ghz Core 2 Duo with Mac OS 10.6.7. I recently tried to partition my drive with disk utility but got an error. I googled the error, and people recommended verifying my hard disk with Disk Utility. I tried this and got this message:

This disk needs to be repaired. Start up your computer with another disk (such as your Mac OS X installation disc), and then use Disk Utility to repair this disk.

Looking at the Disk Utility Log, I see this:
Invalid directory item count
(It should be 32 instead of 30)
...
The volume Macintosh HD was found corrupt and needs to be repaired.
Error: This disk needs to be repaired. Start up your computer with another disk (such as your Mac OS X installation disc), and then use Disk Utility to repair this disk.

So I pulled out the system DVD that came with my computer (scratchless and never used before), and tried to boot from that. I tried booting holding C, changing the boot disk, and running the installer file then clicking restart. All of these lead to the same spot: I get a boot chime, then the DVD spins for a minute or two. Then it stops. The Apple logo never comes up. The computer just sits at the white screen forever (I've left it up for 20+ minutes).

I also tried booting from my GF's DVD (she has an older aluminum macbook), and with that I run into a different problem: the machine boots to the apple logo then kernel panics.

I can't figure out what the problem is. The computer runs absolutely fine when I boot it from the hard disk, but I want to make a disk partition (I want to try running Haiku OS), and besides, it makes me nervous to keep running on a disk with issues.

I've tried resetting the PRAM and the PMU. Neither of these give me any luck.

CDs and DVDs load and run fine otherwise.

 

[Makosuke]

There are two obvious possibilities I can think of: Your optical drive is failing or has a dirty lens, or you got a bum OS restore disc with your computer (it does happen occasionally). The kernel panic when you try to boot from the DVD from an older Mac is probably normal, since it lacks the drivers necessary (it could also be a symptom of a bad drive, but at best you would have gotten a "this disc cannot be used with this Mac" error).

You say that the drive works fine otherwise, so that makes a bum disc the most likely. Did it ever work--that is, did you ever reinstall the OS or boot from that disc?

The easiest way to be sure would be to come up with another system disc from the same model of Mac and see if that works, which would confirm that it was your disc, not the drive. Alternately, you could try using Disc Utility to make an image of the system DVD that's causing trouble and see if it throws up read errors; that's a way to check if the whole disc is reading ok without booting with it.