Success!

["David A. Patterson" <sdpatt2 at gmail dot com>]

To review:

Had x hanging on logout to gdm, using 2.6.11.7 or 2.6.11.9 kernels and
the latest fglrx kernel module + driver.

Tried massive reconfiguration of desktop using Ubuntu's xorg driver -
same behavior :(

Threw everthing back on in the old order of things, and started mixing
and matching kernels and older drivers/kernel modules.

found the sweet spot with a 2.6.10 and the 3.14 driver/module
combination.

This is on an old Compaq 5730th with a Radeon 9700 pro.  Appears to have
intel AGP.  Now I'm looking for the chicken/egg conundrum: was it the
kernel, the generic 386 bus switch I threw on when configuring it, or
the kernel fglrx module?  Sadly, I used a shotgun approach because my
wife needed to get her work done.

Will post with definite results when they're finalized.