I'm beginning to suspect you are correct.
This will be the third time I've had to take the same action in the past year or two. I'm glad I have this MacBook Pro running Mac OS X v10.4.7 to use while the PC is down.
The WinXP PC is my main computer for business use, and the Mac is for video editing and such.
So what did you do the other two times? ;-)
I agree it's the hard drive.
The only way we could get to his data was to boot with Knoppix. We sucked the data off across the network. Once his system was rebuilt, we pulled the data back across. If your Mac has an sshd daemon running, you could pretty much do the same thing.
The same thing happened to me with a brand new Dell XPS. I lost the boot sector twice in six months. I had to have Dell send me a new hard drive.
However, I was able to reinstall Windows XP as a new install in a new partition (or was it a repair install?). Anyway, don't delete the existing partition -- that preserved my data. Then, I was able to back up all of my existing data before reinstalling the OS fresh. Of course, I did all this after the first loss of the boot sector (before knowing that it would happen again).
Since replacing the HD, it never happened again.
-PJ