Pick the articles that make sense to you and be sure to inventory the machine so you know what drivers you need before the format. But I'll share that a format is rarely required. Repairs are easier for me...
http://www.google.com/search?&q=how+to+install+windows+98
http://www.kids-online.net/learn/fdisk.htm
The message "BootSector Write ! VIRUS: Continue? [Y/N]" is because you have set your BIOS to give this message. Installation of an OS often fails when BIOS bootsector virus protection is enabled.
Bob
I just reformatted my computer and it seemingly went well. I now go to reinstall Windows 98 SE and to my dismay a message pops up "BootSector Write ! VIRUS: Continue? [Y/N]". I select yes and it continues further into the installation, when the question is repeated. Here the computer freezes and no further apparent work can be done. What can I do about this? If I just cleared out my harddrive may I still have a virus? Thanks for any help.

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