hi,
 
you wrote:
>The problem is , when reboot the linux system after install it show LI at the prompt >not LILO. I have to use a boot disk to login .
 
few things to check:
1. disks only boot "linear" . try choice in lilo.
2. old boot record unerased:
    to solve :
    - boot from dosfloppy
    - "fdisk /MBR"
    - reinstall lilo
3. lilo not installed right, reinstall.
 
maybe that helps
 
dan