win 2000-D101GGC desktopboard problems

I have recently purachased a PC with D101GGC/p42.66GHz/80GB SATA hard drive. I am having a lot of problems with Windows2000. The CPU usage always shows 100% . the system hangs when i try to run two programs at the same time. for ex, when winamp is running and I try to copy some thing, the winamp hangs. Also explorer stops responding. Let me know how to install windows 2000 D101GGC/p42.66GHz/80GB SATA hard drive??

thanks,
Sameer