For your Windows 98 to come back, I'm sorry, but you will probably have to format and reinstall Windows 98. Once you have installed another "newer" version of Microsoft OS, unless on a seperate partition, and shows up in the boot menu with the other OSs you cannot go back unless you format and reinstall. You can check out this link http://guide.vsnl.ne...s/kushal/win2k/
From reading your log, Windows 2000 will read the Windows 98 files in a backup, but you will not be able to restore the files if you are now running 2000.
If I were you, and you are not having any problems with booting into Mandrake or 2000, I would leave the system alone. Both OSs are giving you better features that Windows 98 can, such as NTFS partitions, file and folder security, yadda, yadda.
I am suprised that you are having these issues, I have installed Windows 2000 and Mandrake myself onto my laptop, let LILO configure the boot menu and never had issues like this.
Hope some of this helps