Fujitsu PC running Japanese Windows XP. Our machine is not loaded with much extra software.
From time to time, usually once or twice in a 3-hour session, the machine will freeze with two bottom-menu items highlighted. Ten seconds pass, it’s good again.
Happens to me, especially when moving/deleting a large file in Windows Explorer. I’m suspecting it’s something to do with the page file hitting the maximum, but I’m not sure yet.
I had a scanner that caused similar problems for my machine. Uninstalling the software fixed the problem. If you don’t have a scanner hooked up, you might try running a program that removes spyware to fix the problem.