Inputs Frozen on startup

[Patton Echols]

I have an intermittent problem when booting my netbook. Startup will 
occur normally, until I get to the login screen showing my name.  When 
the problem occurs, touching the mousepad will do nothing, no key 
presses do anything, Ctl+Alt+f2 does not give terminal.  If I press the 
power button, I get a menu for shutting down the system, but can's 
select the option, enter to confirm or anything else.  The only choices 
are to wait for the shutdown menu's 60 second timer, or hold down the 
power button for 7.  An immediate second attempt is usually successful, 
though last week I had to try twice.

If the mouse moves at the login screen, everything behaves normally and 
the system is stable.

I found these threads that are the closest, but not quite I think and 
don't seem to resolve anyway.

https://bugs.launchpad.net/ubuntu/+source/gdm/+bug/113067
http://ubuntuforums.org/showthread.php?t=1448920
https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-ati/+bug/519705

The Netbook is a Asus 1005PEM Running  Karmic 64 bit, w/ all updates 
applied.  If anyone has experience with this, knows of a better way to 
search than "ubuntu login freezes", I'd be grateful. 

Thanks,

--PE