Your message is missing pertinent info. Example: you saw that line by using msconfig or another utility that shows the Run keys in the registry.
That line is related with a dump file generated after a crash. It can be generated by windows XP itself or another third party application that conforms with the Windows Error Reporting API.
You can delete that line. After that, you can configure to not create a dump file. For details, uncheck all the boxes shown in the bottom of Q320299 -" Windows XP restarts unexpectedly or restarts when you shut down the computer" article.
Trying to unweave, unwind, unravel
And piece together the past and the future,
T. S. Eliot
What is "%systemroot%\system32\dumprep 0 -k", and do I need it? Or should I be in the security forum? I Googled the phrase but I am still confused.