Deciphering OS X boot messages?

Question

If I attempt to boot up my dual 1.25 GHz MDD G4 (fw800) in verbose mode I get the following:
---- BEGIN -----
Darwin Kernel Version 9.2.0: Tue Feb 5 16:15:19 PST 2008; root:xnu-1228.3.13~1/RELEASE_PPC
standard timeslicing quantum is 10000 us
vmpagebootstrap: 317134 free pages and 10546 wired pages
migtable_maxdispl = 79
Extension "com.apple.driver.AppleMacRISC2PE" has immediate dependencies on both com.apple.kernel and com.apple.kpi components; use only one style.
Loading security extension com.apple.security.TMSafetyNet
calling mpopolicyinit for TMSafetyNet
Security policy loaded: Safety net for Time Machine (TMSafetyNet)
Loading security extension com.apple.nke.applicationfirewall
Loading security extension com.apple.security.seatbelt
calling mpopolicyint for mb
Seatbelt MACF policy initialized
Security policy loaded:Seatbelt Policy (mb)
Copyright (c) 1982, 1986, 1989, 1991, 1993
The Regents of the University of California. All rights reserved.
MAC Framework successfully initialized
using 6553 buffer headers and 4096 cluster IO buffer headers
---- END ----
Nothing happens beyond this point.
If I reboot using command-S I get a message about no thermal sensor found and finally it stops as well.
If I boot using the provided Apple Hardware Test it boots up, I can then run the long test in a loop for 24 hours with no errors.
If I boot using Fedora 9 linux DVD it works.
If I attempt to boot using 10.2 - 10.5 DVD the machine stops working.
Any ideas?

Answer 1

Reinstall OS X without erasing the drive
Do the following:
1. Repair the Hard Drive and Permissions
Boot from your Snow Leopard Installer disc. After the installer loads select your language and click on the Continue button. When the menu bar appears select Disk Utility from the Utilities menu. After DU loads select your hard drive entry (mfgr.'s ID and drive size) from the the left side list.  In the DU status area you will see an entry for the S.M.A.R.T. status of the hard drive.  If it does not say "Verified" then the hard drive is failing or failed. (SMART status is not reported on external Firewire or USB drives.) If the drive is "Verified" then select your OS X volume from the list on the left (sub-entry below the drive entry,) click on the First Aid tab, then click on the Repair Disk button. If DU reports any errors that have been fixed, then re-run Repair Disk until no errors are reported. If no errors are reported click on the Repair Permissions button. Wait until the operation completes, then quit DU and return to the installer.
If DU reports errors it cannot fix, then you will need Disk Warrior and/or Tech Tool Pro to repair the drive. If you don't have either of them or if neither of them can fix the drive, then you will need to reformat the drive and reinstall OS X.
2. Reinstall Snow Leopard
If the drive is OK then quit DU and return to the installer.  Proceed with reinstalling OS X.  Note that the Snow Leopard installer will not erase your drive or disturb your files.  After installing a fresh copy of OS X the installer will move your Home folder, third-party applications, support items, and network preferences into the newly installed system.
Download and install the Combo Updater for the version you prefer from support.apple.com/downloads/.