Locks up with Color wheel. OS X Tiger

Laptop: MacBook Pro
OS X: Tiger (with current updates)
Memory: 2 gigs
HD space: 41.9 gigs free

Problem: At random times, although seems like seconds after I boot up, I get the color wheel and cannot do anything. I do have mouse control. When I click on the desktop the menu does go to FINDER but cannot access any menus. I cannot open any hard drives or access the dock. If I am lucky to get as far as opening up an application like Safari and the color wheel pops up, I can switch between FINDER and SAFARI menu with the mouse by clicking on either the open Safari window or on the desktop but the color wheel is still there.
Other info:
* I have to hold the power button down to shut off the laptop
* Already booted to the OS DVD and ran "repair disk"
* Cleared cache folders
* I can boot to Windows (which i am in now) and no problems
* Have disconnect the power plug and battery.
** All of these tasks have not solved the problem

I am currently in Iraq so going over to the nearest Mac store is out of the question.
Are there any software that is downloadable that could help? Or possibly diagnose the problem?

I just recently switched from PC to Mac (LOVE IT!!) so this is new territory for me.

Any help, thoughts, suggestions would greatly be appreciated.
Thank you.

I would like to add that I figured out how to boot into Safe Mode and even though it's slower than the regular running OS, I have not experienced the "Beachballing" effect.

*Thank you eraserhead for teaching me a new term*

Yes, I was able to get into Activity Monitor for a few minutes but then the Beach Ball came back up so now I am in Safe Mode again.

Are there some things I can check in Activity Monitor that will help?

CPU Usage:
% User: 0.00 - 1.00
% System: 0.00 - 1.00
% Nice: 0.00
% Idle: 98.5 - 100

Memory:
Wired: 161.16 MB
Active: 149.32 MB
Inactive: 204.27 MB
Used: 516.29
Free: 1.50 GB
VM size: 6.27 GB
Page ins/outs: 32804/0

I hope this is what you were asking for.

I'm not sure what happened but now the OS is working just fine. Thank you for helping me out though. I do appreciate the all the help.

Thank you.