Okay - in the last two startup, my machine has displayed a flashing folder with the alternating graphics of a "?" -questions mark and the "OS faces" icon. I haven't done anything recently nor have I updated any software. It does continue to start up after a while. Any suggestions?
For whatever reason, It's having trouble finding the startup disk/system folder. It's not usually something that goes away or gets better all by itself, Sometimes it is fine if it boots once and then fixes itself, but in your case (happened twice) that doesn't seem to be the case.
You should probably get on the troubleshooting pretty quick, these things rarely get better. it may be a simple file corruption or it may be more serious.
It usually happens after a hard shutdown or some other situation where there is info in memory that hasn't been written to the HD when an abrupt event stops that from happening. It can also happen if there's been file corruption, if you've changed hardware, if an IDE drive cable is loose or a PCI card is loose, bad RAM or poorly seated RAM, a failing Hard Drive, if you've inadvertently changed something in OSX while booted into OS9, and the like.
Repair permissions, run Disk Utility's repair routines, and perhaps check your hardware connections to be sure they are well seated.
If you have the Hardware Diagnostic CD that came with the computer, boot from that (C key during startup) and run the tests to check for a hardware issue.
You should probably run software update and get 10.2.8, but do the maintenance first. You may end up doing an OS reinstallation.
You may also want to try zapping your PRAM by holding down the command + option + P + R keys during bootup. Allow the system to chime 3 times and then release the keys. Another thing to try is to hold down the option key at boot up. This will make the system search for bootable devices.
Could be your 'Finder' or 'System' file in the System Folder...
I would recommend booting from your system installer CD, then run the Apple Disk First Aid utility.
If that doesn't work out either dragging and dropping the Finder and System file back onto your system folder from your install CD or run OS 9.2.2 updater again (or whatever OS version you're running) over the top of your present system, this generally installs a fresh Finder and System file but keeps your previous prefs active.
I would also recommend killing your desktop Db. (Not just rebuilding) - Use either Techtool lite or a util like 'Filetyper' to make your Desktop Db files visible (they're invisible by default) - trash them and restart. Sometime the system cannot read the desktop Db file due to corruption. The location of files are stored in this Db file and if it becomes corrupt, it can prevent your system from finding the necessary file(s) for startup.
If all else fails and you don't want to try re-installing your OS, I would use either Diskwarrior or Norton Utilities to fix your system directory related weirdness.
Although, the best possible solution would be to reinstall your OS if you still can't boot your system folder after using AMV'S PRAM zapping advice...
Even a blind squirrel finds a nut once in a while...