How is you son cutting the power? Is he just pressing the power button or using a power strip to literally turn it off. Unplugging it perhaps?
If he's pressing the power button, you can set Windows XP to safely shut down automatically. It will be equivalent of pressing ALT-F4 to exit what ever programs are running and then clicking on Shutdown and Turn Off. But it does it all in one shot very quickly. This will shut it down properly and prevent the errors coming up when you first start the computer.
You can enable this feature by going to your control panel, performance and maintenance, power options and then click on the Advanced tab. There you will see a section aptly named... power buttons. Change the drop down to say "Shut down". Now it's all set so that when you press it, it will shut down completely.
Hope this helped.
~ DeLuSioNaL