Boot problem: kmode exception

I have started having problems booting into Windows 2000. The whole build is fairly new, but I had not done any major installations recently. The night before the problems I think we had installed Microsoft Chat and Yahoo Games applets. I had also used the Hibernate state for the first time the day before the problem occurred.

So what happens is during boot up it goes through the regular startup screens, it then runs checkdisk, and then I get the blue screen. It reboots so quickly that I can't read it, but I have been able to determine that it reads 'kmode exception not handled'.

I've run repair to no avail. I've updated my BIOS. But I still cannot boot up, in any mode (safe, VGA, etc.). Any ideas on how I can proceed? Do I need to reinstall? Do I have to reformat and reinstall (argh!)?

 

MS KB describes possible causes as:
Hardware failure (memory, processor, or motherboard).
Anti-virus software that is running on your computer.
Services installed by third-party software.
So, is likely an offensive applet. How to get rid of it, since you can't even boot into safe mode, is beyond me.