First, find out if your PC hardware is working:
1) can you boot to the BIOS?
2) does MEMTEST pass? www.memtest.org (one full pass)
3) Optional test: can you boot to an Ubuntu DVD? (this tests everything but your hard drive)
You can burn an Ubuntu DVD on a different computer for free (though it asks you to pay) from the Ubuntu website. Just boot to that and run (not install) it from DVD.
If your hardware works, then normally you do a System Restore unfortunately since you keep crashing this is likely not possible. If it was a hardware issue and you resolve it then Google how to do a System Restore to the last restore point (assuming you have one).
*Another alternative is to restore the Hidden Image, but if you installed XP yourself you won't have one. That's on pre-built systems. If you have one, and restore it, it will replace your current XP setup so everything is gone.
I would need more feedback regarding my tests to help further.
Thanks for the help photon boy. I yanked the PC and hooked up a m**book just to stay connected when the last try to boot did not even get into BIOS. I'll plug it back in, try it again and see what happens. If no joy I'll try the linux disc and see if that will at least let me look at the hd to try and save data.
I'd read on some of the forums that many folks got Borged when Comodo sent out a major "update/upgrade" back in April. Previously I'd only allowed the firewall to be installed and updated. Don't know why that would have killed the boot up, but then I don't know a lot of things. If you've heard of anything about this I'd appreciate your thoughts.