PC hangs after XP SP2 installed

I installed XP SP2 a few weeks ago, and since then my PC hangs, but not at the same spot. I regularly run SPYBOT S&D and Ad-Aware and I use Black Ice as a firewall.

My PC has an AMD Athlon™ XP processor 3200+; 512MB PC2700 DDR memory.

Any ideas?

Thanks!

 

Define hang

It may be random, but give some examples of when it did hang.

Did it hard lock? Did the mouse still respond?

 

Nothing would work, mouse, keyboard, etc. Complete lockup. Only option is to unplug the power cord for a hard boot.

 

Does it do it in Safe Mode?

 

Haven't tried Safe Mode, should I give that a shot?

 

I would. Tells us if its the OS or something installed.