My fan is very noisy what can this mean? I'm getting very bad gameplay. I can't play every other 2 minutes because the game freezes up and goes into a slow motion state. I haven't considered the loud fan. Any help?
Also the game I'm trying to run is Counter-strike, which has very low system requirements.

System specs:
Compaq Persario
Intel Pentium 4 1.50GHz
40GB HD
512 RAM
nVIDIA 16MB Video
Microsoft Windows XP Home Edition
12x DVD-ROM
12x CD-RW

Are you able to identify which fan it is? CPU fan? Chipset fan? Case fan?

You need to replace that asap. It may be the cause of your woes. If your computer is overheating to the point of producing errors, it is dangerous to your system.

Download this program and watch your temps: http://www.techspot.com/downloads/26-motherboard-monitor.html

It could also be your video card that is overheating, which I don't believe that software watches, but still you should see some high temps on your chipset if your vid card is getting that hot.

Not sure which fan is making all the noise. I think its the biggest one in the back of my tower at the top side. But it is louder then my refrigarator.

I'll check out the temps and post back.