Tks for your advice.
I would suggest another way around, use the one in the repository instead of from mozilla.com. I have 126.96.36.199 for i386 from the repository installed but haven't seen anything like what you described. I would try to remove Firefox from your system, then delete ~/.mozilla and /usr/lib/firefox-1.5.0.x directories and re-install from apt-get.
Whether remove the existing firefox with;
$ sudo apt-get remove firefox
$ sudo rm ~/.mozilla
Then which directory shall I remove
$ sudo rm -rf /usr/lib/firefox
$ sudo rm -rf /usr/lib/mozilla-firefox
$ ls /usr/lib/ | grep firefox
After installation of Ubuntu-6.0.6, I have run
$ sudo apt-get upgrade
In case you want to trace what went wrong when it crashed, try,
sudo echo "core" > /proc/sys/kernel/core_pattern
ulimit -c unlimited
Yes, I'll if the PC won't hang.
I just tested;
~$ sudo echo "core" > /proc/sys/kernel/core_pattern
bash: /proc/sys/kernel/core_pattern: Permission denied