Start up problems with Jag/eMac

Question

I'm having problems with my eMac starting up with Jag (latest version). BEHAVIOR: It hangs after the gray Apple, after the blue screen with the extensions and gives only a blue screen (mouse in upper left hand corner of screen) and appears to blink to a slightly lighter blue screen then back.
Here's what I've tried.
1) Boot to Safe Mode (hold down shift key right after start up chime). Results: gives gray Apple, blue screen with extensions loading showing 'Safe' then blue screen as in BEHAVIOR (above).
2) Boot from OS X Jag install disk (hold down C key after start up chime), run Disk Utility to Repair Permissions & Repair Disk. Results: permissions repaired; disk repaired (but gives msg 'overlapped extent allocation file 1294823d/1294824d" even when Repair Disk done at least 2x, probably 4x). Restart gives BEHAVIOR above.
3) Boot to the OS 9 install disk (came with computer). Results: starts the install CD but I get error message that hard drive cannot be mounted and asks if I want to initialize (which I don't).
4) Zap PRAM (hold down Cmd-Opt-P-R as I power up, wait for 5 chimes; then restart). Results: see BEHAVIOR above.
5) Boot in Target mode (hold down T after start up chime). Results: able to mount the eMac hard disk on my iBook (Panther) and recover files. Ran Repair Disk from the Panther Disk Utility on the mounted eMac hard disk (found the same 'overlapped extent' error message found above). I get the message "The volume eMac HD was repaired successfully. Repair attempted on 1 volume HFS volume repaired." But on reboot, I get the same BEHAIVIOR above.
6) Hardware test (from CD that came with eMac, ver 1.2.1) was run. Results: all passed (ran it 2x with same results).
Is this one of those 'overlapped' problems that nothing else will (easily) will work except a) backup files (via FW) and b) erasing hard disk and reinstall?
Is Disk Warrior really that good? Good enough to fix this without having to back, erase and reinstall the OS?
Thanks,
Richard
eMac   Mac OS X (10.2.x)   multiple systems

Answer 1

Thanks for the Apple doc. I followed the directions (new terratory for me) and successfully removed the overlapped files. But my system gave the same behaviour (wouldn't start up), even after the overlap was not detected via Disk Repair or fsck).
So I did an erase and install (after backup via target mode) from my system disks, downloaded all the updates, etc. And I can get a system start!
But now I cannot add a printer to the Print Center. Argh (never had these kinds of problems with Macs before; usually an erase/install cures all).
I've repaired permissions, run everything I can find with the Printer Center Repair v. 3.0.3 from www.fixamac.net, rebooting after everything tried. Still the Print Center unexpectedly quits when I try to add a printer.
I'm poking around the Printing & Faxing discussion group but not turning up anthing that works. Any Ideas?
Richard