Make sure that machine boot from Cd-Rom.
How to Know Machine boot from Cd-Rom?
After start computer
Continuously Press “Esc” or “F2” or “F1″or “Del” key on keyboard
enter bios setup
Go to Boot order
select boot option for boot the machine from this drive.
i.e Floppy Drive Or Cd-Rom or Hard Drive
suppose we can choose a Cd-Rom drive means machine boot from Cd-rom
Insert windows 98 Bootable Cd into Cd-Rom
save and exist bios setting
after existing Bios ,the computer will restart and booting from Cd-Rom
Microsoft Windows 98 Startup Menu Windows open
shown is 3 option we can choose “start computer with Cd-Rom support”
When if finishes loading, you will see the above screen with A:.
Type fdisk and then press enter
next window ask for enable large disk support
after enable large disk support
then choose display partion setup information
delet non-dos partition
then given a format command
i.e A;>format c: /s /q
after formating the machine
use following command for Grub uninstaller