Sounds like its crashing... Start it from a terminal and leave it running there
so you get all of the console messages from it running. That should give you
some output to debug.

That or you could edit the launcher command to redirect output to a log file to
get the same effect without the clutter.

When I run a lot of apps on my ubuntu box, it gets goofy. I only have 512k
ram. It loads up quite fast. I can only run a couple of things at a time.

I hope you meant to write "512M ram". 512KB is less than even the old
DOS systems from the early 1980s -- they had 640KB RAM. :-)

One of my oldest Linux systems is RedHat 4.2 circa 1996 running on a
Sun IPX 4/50; 64MB RAM and a 40MHz SPARC CPU (actually 80MHz since I
replaced the stock CPU with a Weitek "PowerUP" frequency-doubled).

I still have three functional AT&T 3B1 (aka UNIXPC aka PC7300) systems.
Motorola MC68010 CPU with 4MB (yes, that's four) RAM. It runs the full
AT&T SVR2 and I used to show these off at the West Coast Computer Faire
running gcc, emacs, and the asteroids games all at the same time. Hard
disk is only 80MB. These are actually kinda neat: "futuristic" wedge-
shaped chassis, builtin tilt'n'swivel monitor, 3-button mouse, and
even a keyboard garage. They still make great props for sci-fi movies.

Are you running the beagle-thunderbird extension? I had a similar
problem and tracked it down to that. Disabling beagle in thunderbird
cured the problem.

I'd agree - i've found Thunderbird stable apart from when i tried an
.xpi plugin/extension. If not beagle perhaps another.