random lockups

I have a 3 1/2 month old build that is randomly locking up. The cursor will move around the screen but will not highlite anything or open anything. the keyboard is useless when this happens also. Sometimes happens in between progams other times is just locked up when you walk up to it. it will start the monitor but thats it. It has even locked up on the welcoming screen, I walked away for 15-20 minutes after turning on the computer and when I tried to access my account nothing would work. here is the hardware list and settings.
http://www.newegg.com/Product/Product.aspx?Item=N82E16813128394
http://www.newegg.com/Product/Product.aspx?Item=N82E16819103688
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231098
Windows xp pro
did have 3 accounts but have removed the other 2
no hibernation only turns off monitor
Any help would be Great!!
kurt