NOT BOOTING FROM CD ROM

Hello,

I had made Windows XP SP2 as Customized CD for installation, All this I did by copying OS content to harddisk and just added a file...inorder to that nothing I've changed.

I've burned the same folder to NEW CD (Customized CD) and changed the bios setting as 1. CD ROM, 2. HARDDISK. On booting no message is shown "Press any key to boot from CD" Instead, booting is done from HARDDISK why?

But when the original CD is kept it is booting from it.

Again the changes what I tried are:

1. Created an image of NEW CD (Customized CD) & burned on another CD then it is also not detected.
2. Kept on different System still not detecting.

Kindly, any one help me in this issue...

What all the changes I need to make & what mistakes I've done

Thanks & Regards
Wazy.