I think that your computer was updating your registry because of the new program installation and you just happend to reboot the machine before it was completed. Thus, when the machine rebooted it found registry errors.

If you are using Windows98 the best free utility to fix this problem is Scanreg.exe (already on your hard disk from when you installed win98). Sounds like Windows has already run scandisk when you rebooted after the crash and restored your previous registry.

If you wish to even go back further, Scanreg keeps a back up copy of your registry from the past few days (I think it's 5). Load or boot to a dos prompt and type, "scanreg /restore" (no quotes) and then pick the copy of the registry you want to restore.