Youtube.com/johnsonyip1 for more Linux help video
I will teach you how to use ImgBurn which is a free CD burning program for Windows which can also rip CD ISO from Install CDs like the Ubuntu Install CD. You can use ISOs to install Ubuntu on a virtaul machine like virtual box, VMware, Virtaul PC and other virtualization programs. ISO are also a great way to backup your Linux install CDs since ISOs do not get scratched or damaged by water like CDs since ISO are digital meaning you can put them on a thumb drive, web server, and other drives.