Startup manager won't show ANY volumes

Your operating system is hosed. Files required for startup are either missing or corrupted. You will have to reinstall OS X. If you have a backup then erase the drive and restore your backup. If you don't have a backup then you can:

How to Perform an Archive and Install

1. Be sure to use Disk Utility first to repair the disk before performing the Archive and Install.

Repairing the Hard Drive and Permissions

Boot from your OS X 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 Installer menu (Utilities menu for Tiger.) 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, then quit DU and return to the installer.

If DU reports errors it cannot fix, then you will need Disk Warrior (4.0 for Tiger) and/or TechTool Pro (4.5.2 for Tiger) 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. Do not proceed with an Archive and Install if DU reports errors it cannot fix. In that case use Disk Warrior and/or TechTool Pro to repair the hard drive. If neither can repair the drive, then you will have to erase the drive and reinstall from scratch.

3. Boot from your OS X Installer disc. After the installer loads select your language and click on the Continue button. When you reach the screen to select a destination drive click once on the destination drive then click on the Option button. Select the Archive and Install option. You have an option to preserve users and network preferences. Only select this option if you are sure you have no corrupted files in your user accounts. Otherwise leave this option unchecked. Click on the OK button and continue with the OS X Installation.

4. Upon completion of the Archive and Install you will have a Previous System Folder in the root directory. You should retain the PSF until you are sure you do not need to manually transfer any items from the PSF to your newly installed system.

5. After moving any items you want to keep from the PSF you should delete it. You can back it up if you prefer, but you must delete it from the hard drive.

6. You can now download a Combo Updater directly from Apple's download site to update your new system to the desired version as well as install any security or other updates. You can also do this using Software Update.

Yes, that's correct. You can eject the disc by restarting the computer and after the chime hold down the mouse button until the disc ejects.

You will need to use the OS X Installer Disc that came with the computer. In order to start up from the Installer Disc you should insert the disc into the optical drive then restart the computer. After the chime press and hold down the "C" key until the spinning gear appears below the dark gray Apple logo.

If you cannot startup from the Installer Disc then you may have a bad disc, a bad optical drive, or more serious hardware problem. I you have an Apple Hardware Test disc you can boot from it and run the diagnostics. If you have an Intel Mac then you have to boot from the Installer Disc One in order to run the hardware tests.

Follow the steps in the order they appear. I'm not sure what it is you are confused about.

Is it an Intel? If so it's on the Installer Disc. I don't know about the PPC model.

Did you try ejecting the DVD?

You might try booting into single-user mode by restarting the computer and after the chime press and hold down COMMAND-S until a black screen with white type appears. At the prompt enter:

/usr/bin/drutil eject

Then press return.

Enter:

reboot

To restart the computer.

If you boot with Option held down, Command-. (Command Period) opens and closes the optical drive. The eject key doesn't work in that mode.