Update 2007/10/26: My Windows XP partition suddenly died (became unbootable) while I wasn't even using the computer! No boot option would work (safe mode, etc.). The boot would progress to a blue screen showing some unreadable error message for what looked like a millisecond, and then automatically reboot. I couldn't find any way to stop the reboot and see the error message.
I tried out my HP Pavilion ``system restore'' disk, and it was unable to repair the system and instead insisted that I wipe out my entire Windows XP partition and start over from scratch.7 I probably could have used the GNU partition-guessing tool gpart to detect my Windows partitions and refresh the Master Boot Record (MBR), etc., but instead I went ahead and rebuilt the MBR and partitions from scratch using the HP system-restore disk.
Since the system restore did work ok, this is more evidence that the spurious 1GB partition I deleted (logged above) was not missed (unless that's where it kept a backup of the MBR ).
Also happily, the system restore did not change any disk partitions, so that my Linux partition was not altered. However, the Linux boot loader is no longer accessible, so I will have to either rewrite the MBR, or edit boot.ini (used by Windows for booting). Since I've heard that it's dangerous to alter the MBR (could this have been my problem after so many months of trouble-free dual booting?), I plan to use the boot.ini method next time around. However, for now, I am so annoyed with Windows in general (especially for crashing so hard that I have to build a new system from scratch after less than a year), I plan instead to move to MacOS-X and obtain Windows compatibility using something like Parallels or VMware Fusion to run Windows in the MacOS environment. The HP Pavilion will make a nice Christmas present for my mother.
[Update 11/18/2007] Ok, I needed to fire up my Linux partition, so my trick was to upgrade it to Fedora 7, figuring I could rewrite the boot loader in the process. Unfortunately, the upgrade crashed before it finished. I think the problem has to do with an unreliable DVD drive. (The laptop often will not boot from DVD, and it seems to be very sensitive to power-supply voltage. For example, one of my tricks to get it to boot from DVD is to remove the power connection, which presumably removes all ripple from the supply voltage, and perhaps lowers the voltage a little.) I restarted the upgrade, and it appeared to finish ok. However, after rebooting, yum would not run because its ``rpm'' module was missing. I tried synaptic, which found 49 ``broken'' packages, but it could not fix any of them. Then I thought, ``hey! Fedora 8 is out!'' So I downloaded a Fedora 8 DVD image via the torrent and burned a DVD-R for that. I plugged my laptop into its own dedicated power circuit (maybe the other circuit was ``dirtier''?) and booted off the F8 DVD. The anaconda installer crashed in some python script very early on.
After a little searching in the Fedora mailing list archives, I retried the F8 upgrade in ``text mode,'' and that went better. The next snag was that the anaconda installer said it could not update the boot loader (due to ``system changes''), but it would let me skip the bootloader update, or write a new bootloader. I selected ``write a new bootloader'', and that crashed. Ok, let's try ``skipping'' the bootloader update--the upgrade to F8 proceeded smoothly after that. Upon reboot, lo and behold, the linux kernel was the F8 kernel! The existing bootloader (in the MBR) just worked? I guess that means there is no kernel-specific info in the MBR boot-loader; hooray for orthogonal engineering. After the upgrade and reboot, yum -y update worked just fine, and I'm back in business.
I should mention that before the F8 upgrade, I moved planetccrma.repo from /etc/yum.repo.d/ to /etc/yum.repo.d-hold/. I did this because I noticed that most of the ``broken'' packages in the F7 upgrade were PlanetCCRMA packages. Later I also had to yum remove planetccrma-core because it was specifically tied to F7; it's just a meta-package so removing it does not cause any actual packages to be removed.
The only ``problem'' I noted with the upgrade to F8 was that my display resolution was capped at 800x600. Feeling relatively foolhardy (but backed up), I set enabled=1 in /etc/yum.repos.d/fedora-updates-testing.repo in order to try the very latest updates (of which there were 247). This took me to release ``F8.9'' which evidently includes the various versions of F9 packages under development. The good news is that my screen-resolution problem went away. The bad news is that I lost my mouse! The mouse just sat in the middle of the screen whether I tried the touchpad or the external USB mouse. If I exited X windows (via control-alt-backspace), I got a standard command-line login prompt and a working text-mode mouse! This is not good. I next tried to ``upgrade'' to F8 again (actually a downgrade). This went suspiciously quickly, leading me to think nothing happened, but something happened because then the Linux parition wouldn't boot (grub printed ``file not found''). I rebooted the F8 DVD again, selecting ``rescue an existing installation'' and looked at boot/grub/grub.conf, and sure enough, it only listed kernels that were no longer there. The F7 and F9 kernels had apparently been deleted by the F8 ``upgrade'', but grub.conf had not been rewritten to point to the F8 kernel that was installed. (In fairness, I did ask to skip updating the bootloader, because no other option would work.) So, I edited grub.conf to point to the one and only kernel in /boot, and the reboot went fine. Now the problem was no mirrorlist.txt in /var/cache/yum/(fedora|updates), so yum update would not run. Evidently, enabling the F9 test updates deleted mirrorlist.txt from fedora and updates! I ran synaptic which reported 6 broken packages (sounds pretty simple), and noted that I had two copies of avahi. I then yum removed the F7 version of avahi, leaving only the F8 version. Finally, I copied /var/cache/yum/development/mirrorlist.txt to the fedora and updates directories, and that seemed to get yum update working again. Unfortunately, that left me with a lot of F9 packages, even though I disabled the fedora-development repo. Miraculously, the system still works fine without a mouse. You learn a lot about a system by mangling it and having to claw your way back to the surface.
I suppose the next step is to re-install the fedora-release package and do a standard yum-based ``upgrade''-- something like yum group base reinstall or the like (I don't want to look it up). Rather than futzing with this any further, I tarred up my home directory, scp'd it to my main Linux machine, freshly installed F8, grabbed my home directory and unpacked it into another directory, from which I mv'd in only what I really want to keep (i.e., standard procedure for a fresh build). I think I could have fought through the upgrade, but I was ready to get it over with. F8 looks pretty nice. However, as of Nov. 21, 2007, Planet CCRMA has a ways to go.