i have a problem with my laptop. here is the specs first of all:

intel pentium 4 3.08 ghz
512 MB Ram
On board intel 345M 64MB gfx
40 GB HDD (about 8GB free)
On board sound card

no internet connections
no lan connections of any kind

the problem started when i tried to play a 2002 game (specifically diablo 2). the game wouldnt even move. when i hit task manager i saw that the cpu usage was 100%. i quit the game, free disk space, defragment, run four different anti virus and anti spyware programs and restart. as soon as i restart i check task manager. only 23 processes running out of which the most resources go to svchost which eats up 16mb and thats it. nothing running in the background, no weird processes that i dont know about, only the basics running. still cpu usage 100% and not dropping for a second. i have a fan that is not working but that is not the problem because it has been like that for more than a year now and it never did cause a problem. the laptop is getting enough air as i have a base that shoots lots of air from below. there. i hope someone can help me because it sucks, i cannot do ANYTHING