I hesistate to post this as there have been so many cases of it before. But I thank those who have and those who've replied because I've tried quite a few things that wre suggested in these forums.
My system: G4/400 Sawtooth AGP running 10.3.9.
Last night, the Finder developed a persistent spinning beach ball. The one window which is open shows all partitions of the HD (Maxtor, installed not more than a year ago). I had had a number of windows open earlier in the day, but I did not turn on the machine on this occasion so I don't know whether they 'disappeared' or were closed before the beach ball arrived.
I can start most apps in the Dock using the dock. Keyboard shortcuts and mouse actions inside the app windows are OK. However, any attempt to use the menu bar causes the app to freeze.
I rebooted using TechTool Pro 4 and ran every test. No problems were detected. Rebuilt the directories. No change.
I rebooted from the Install disk and ran Disk Utility. Verfiy disk detected no problems. I ran Repair Permissions several times on the boot partition. Each time it stopped at the same point and threw an error message saying that it had lost the connection to the Disk Management Tool.
I rebooted with Command-S (whatever you call that mode) and ran fsck -fy. No problems were detected.
This morning I opened a Samba session from my Linux box in an attempt to backup my Mac mailboxes and other sundry stuff. I can access everything but one partition of the drive (not the boot partition). I can access the boot partition without problems. So I suspect that this one partition is causing the Finder to hang. (But that does not account for the Repair Permissions problem on the boot partition, described above.)
I'm currently using TechTool to recover the errant partition (and I hope I can dump it onto a Firewire drive I have connected).
In the meantime, if anyone has any insights I'd be most grateful to hear them. Thanks in advance.