Computer Freezes when USB is NOT in use!

[longhornthinkpad]

This is my first post. I searched and found one other person who has the same exact problem I have but couldn't find a solution: When nothing is plugged in the USB, the system will boot up to the blue windows xp screen and then freeze. When restart with a device already plugged in, it works fine. Lately, somehow it has been able to load up to windows without any USB device (although its still a gamble and not always works) but once I'm in windows and I plug in a device and unplug, same thing happens: it freezes up. I have no idea whats causing this and why its happening now.

By the way, I spilled a small amount of water on the keyboard the other day but most of it stayed on top as the surface tension prevented it from seaping through. I immediately shut off and dried it for a few hours and turned it back on; worked fine except for the USB problem I just mentioned. Now I'm still not sure if this is the cause of the problem since that was the first time in a very long while that I actually unplugged the mouse: I never carry around my laptop and never had a reason to unplug the mouse.
Please help me.

My Thinkpad: T42p 2374-7XU

[BillMorrow]

if it were me experiencing this problem, i would swap the HDD with one that has a factory preload with little or no modification..
if the problem remains, then it is obviously a hardware problem..