I am not certain that I understand all of what you just said. I feel certain that in my explanation I have used words sloppily such as to derail you. I will try again....
GRUB was used as the bootloader. On the subject PC and at the point where GRUB reads from menu.lst, I have the option of choosing to boot into PCLinuxOS (either with or without safemode) or into XP. When the XP option was chosen, the error message would appear. That has been the problem from the onset and it is real to me (and at least a few hundred others based upon my internet research). If the filesystem was not corrupt, then the error message is in error, itself.
Do you really believe that the partition filesystem was not corrupt??
I have no way of knowing, at this point, one way or the other. You only reported what you did after the fact, so there's no way of verifying what you did, or what the actual state of the system was before. If we take your word for it, all we know for certain is there was the appearance of a problem, and it now appears to have been fixed. What the actual problem was is unknown, and that being the case, so is the actual solution. Whether the steps you took were in fact the cause of the fix, or were coincidental to the actual fix is also not a certainty.
Normally when a problem occurs, we have a number of tests we do, in an orderly fashion, to determine what the actual source, and extent of the problem is, and from that information derive a proper means of fixing it, using known and proven methods. Without any verifiable test results, we can only speculate as to what the true condition of the system was, if your actions had any specific cause and effect relationship to the fix, or if it was just a happy accident that the system righted itself, before your actions damaged it further.
The best I can offer at this point is that I'm glad it seems to be working properly now, and I hope it stays that way for you.