Cpu Usage Problem CPU Usage Problem. Please Help Windows XP?

CPU Usage Problem. Please Help Windows XP? - cpu usage problem

Every time I open something on my computer, my CPU usage jumps to 70-100 Beier. What can I do to stop this? I try to play a computer game and start charging me whenver freezes and crashes. All ideas, what can I do? Only recently begun to occur. I closed all my processes. But even when I click to open a Web page that jumps to 60%. What can I do?

Intel Pent 4
512 RAM
2.66
Windown XP