I have had several crashes with Leopard. They are random, never the same application is running. Sometimes Safari, others iPhoto. And still other Firefox.
Any trouble shooting going on for this kind of problem?

Yes… continue.

What does "crash" mean? Does the computer freeze? Do you have to force-quit? Do you have to do a forced restart? Please provide some information about your system (see my signature as an example). What is the hard drive capacity and how much free space does it have?

MacBook Pro OS 10.5.5, 2.16GHz intel, 2GB ram,667MHz bus speed. The drive has 39GB available.

Crash means in this case it shuts down as in turns off. Just like shutdown. It just clicks (audible sound) and the screen goes black.
I need to press the start button to reboot.

Sounds like a hardware problem, but try looking in system.log using
Console.app to see if there are any clues... but i sorta doubt it.
Does the click sound like the disk, or some other physical part?

You can try the links in my sig... but if it's a hardware bug,
they won't help much. if you can reliably reproduce this at
will (or even if you can't, i suppose), take it to an authorized
Apple repair center.

(make an appointment by phone first, just in case).

Two things to try:

1. Look in /Apps/Utils/Console after restarting, and see if there are any pertinent entries immediately before the shutdown.

2. Run the Apple Hardware Test disc that came with your Mac.

I did most of what was recommended. I did disk utility and ran tech tool deluxe.
No stops for the past few days now.
Although I did have one running disk utility.
Keep my fingers crossed or head to an Apple store.

> Keep my fingers crossed or head to an Apple store.

You forgot BACK UP!!!

Do you still hear that click? If it's coming from the vicinity of your HD it is most likely that it's about to fail, so, to repeat, BACK UP!!!

> Although I did have one running disk utility.

Sorry... What does that mean (and did you run AHT)?

No more clicking sound. And no more crashes.
I back up every week which is enough for me.
I have external hard drive connected for backup.
I did not run AHT because if it is a Hardware test I don't have a disk to run it.

> I did not run AHT because if it is a Hardware test I don't have a disk to run it.

One of the discs that came with your MacBook Pro includes AHT; it should be specified on the label.

I'm not certain when things changed, but you'll either find AHT on its own disc (from which it can be accessed with a "C" boot) or piggybacked on another disc (from which it can be accessed by a "D" boot).