Windows XP Safe Mode wont Boot

I don't know when it happened, but I started getting a constant request to reboot from CA Security Suite after an update. It returns everytime I reboot. I checked with CA Support, and the Tech wanted me to boot in Safe Mode with Networking. The process gets to a certain point, and then reboots itself having never gone into Safe Mode.

I have since done a Windows Repair from the CD. I even performed the process offered by reimage.com that is supposed to fix all Windows problems to no avail. I have just completed the Windows XP Cleaning Procedure from this site, and the situation remains the same. Although I like the free tools to maintain my PC, I still would like to be able to boot in Safe Mode.

Can anyone help me?

 

What is the exact file which hangs while waiting on safe-mode bootup?

 

The list of files on the screen hangs with kmxstart.sys as the last entry.