problems caused by the operating system would account for less than 10%
the other 90+% is down to the user and components
run memtest on the ram 1 stick at a time
http://www.memtest.org/
have installed sp1 yet
turn off the auto reboot
control panel /system/advanced/startup and recovery settings
then untick the auto reboot box
post any bsod error messages the computer freezes on in full