Aftet installing the driver for an HP 5100c on Windows 2000 Pro (which failed part way thru install), got a stop 0x0000000a. Found Microsoft article 315377 (formerly Q315377) which advised to start in safe mode and remove HP RecisionScan.
The uninstall ran suspiciously quickly, and on restart still got stop 0A.
The fallback in 315377 was to manually rename EPSTW2K.sys using Recovery Console (I actually did it in Safe mode, command prompt) after which W2k booted without STOP 0a.
I thought all was going to be ok, but that first boot took a long, long time to complete and so has EVERYTHING since. When I say slow I mean that in a command prompt it takes about 10 seconds to echo each character to the screen. Everything seems to run, but 99% of all CPU time goes to this system process. Safe mode has the same problem.
Suspecting the HP driver files, I checked HP's site and based on their driver removal info renamed all files starting with hpsc* or hpsj*
Using process explorer and other tools found that the time is all spent in thread 7 of the system process but this doesnt seem to be a separate driver file. Spent much time tying to find a driver culprit but so far to no avail.
In regedit searched for references to epstw2k but have found one in an MRU entry (not a likely candidate) and is still searching (will probably take overnight)
User has no current emergency disk so I have not tried a recovery yet.