There are quite a few ways of doing this - can you actually boot the machine? If you can, hold the 'ctrl' key during boot, and at the boot prompt select 'command prompt only.' Once at the DOS prompt, you can copy the entire win98 CD onto the harddrive and install it from there.
If you can't boot the machine atall, or don't know how to copy the CD in DOS, then brads instructions will work with one modification. Leave out the 'format' command, but instead type 'sys c:' at the a:\> prompt. This will make the disk bootable without deleting anyting. Then you can follow brads advice about copying the oakcdrom files etc
