I have one of those little E-machine laptops, and it's about ten years old. Every time I turn it on, It'll stay on for about two, maybe five minutes, and the screen will go black, and then turn white. Ctrl+alt+del wont work, it just stays completely frozen.
Could be a video card issue. Given that it's 10 years old, I would say it's time for a new laptop, but you could always try updating the video card drivers or formatting and reinstalling Windows (not Windows Vista/7, I assume?).