Hi, and welcome to PCHF
An ISO is basically an image of a disk, what you need to do is burn that file to CD, not extract bits of it. Fortunately the method of accomplishing this is simple. Freeware software such as
ImgBurn will allow you to burn the ISO to boot from your CD drive with ease.
Make sure the file is intact, it's contents should be exactly as it was when you downloaded it, otherwise it won't work. If you get stuck at any time and need instructions, be sure to post back here. Thanks.
Pgh