CPU utilization?

[archaeolept]

I'm running winxp currently, and an instance of the game may use up to 100% of my dual cores, even when it is doing nothing. For instance, it may be at 100% just on the menu screen - i minimize it, and it stays at 100, or goes to 50; i bring up the window and minimize it again, doing absolutely nothing else, and the cpu usage then perhaps goes down to 0 where it should be...