Backups are good, mmmkay?
I have a win98 SE box that functions as an email/quicken/internet surfing box and also is the gateway to the internet for the rest of my boxes. It's exceedingly slow but is usually reliable. Today at about 11:00am one of my kids hard-rebooted it and the disk got scrambled. The FATs didn't match and a lot of the files had weird EOFs. I cleaned up the disk errors but the box still wouldn't work right. The usual remedy of reinstalling windows didn't work because the installer failed trying to update some .INI files.
So..... gulp..... I installed a junk version of windows onto a temp directory, installed my backup software, mapped a drive to my server holding my recent backup files, and restored the entire \WINDOWS directory.
Then I edited MSDOS.SYS to re-point windows to \WINDOWS, took a deep breath, and rebooted. And it came up fine.
Moral? Do those backups, boys.