If you have a Windows 9x bootup disk you should check first that Boot from Floppy is Enabled in teh Bios - choose the CD-ROM option after the floppy bootup disk sequence has commenced.
The Windows CD should be in the drive.
If you don't have a Windows bootup disk ask around or arrange for the files to be downloaded to a floppy from:
Also, if and when you manage to install 98SE again, don't forget to also install the "Unofficial" but respected 98SE Service Pack from:
which includes all the updates up to late last year and is the final version.