Newer computers are able to support booting from CD, but are often set to look for the Operating System on the hard disk first.
You want to change the computer to try the CDROM instead, before the hard drive.


The first one is used on many laptops. Your computer can allow you to boot from the CD once (only for this time) by pressing a special key (usually ESC or F1, F2, F3, F11 or F10) during the memory checks (very soon after the computer's power on). (It will briefly tell you what key to press, usually in the upper right or left. It is quick so don't be surprised if you miss it the first time.)

The second method is to setup your box to permanently look for a boot-CD at first, and try to boot from the hard disk only if no CD is found. Again, you have to press a key during the startup, which will allow you to enter CMOS/BIOS SETUP - it should say during the boot up sequence.

Then the (usually the second set of options) will include a set of boot possibilities. Change to CD/ DVD or USB (if available)

then save (usually F10) and exit the setup function. (Sometimes you have to exit in order to save, if so you want to choose the save & exit option)

you may need to do a cold-reset or even turn your computer off, to be able to use the new settings.
you should boot from the new option which you can change back to HD later

In the BIOS you can go through some menus and look for "Advanced settings", "Boot order" or "Boot options". Set CDROM as a first device and hard disk as a second one.

All the keystrokes mentioned above are usually written at the computer's display at the time you can press them, or you may find them in the documentation of your motherboard.

A third way to boot from the CD is by using a WakePup floppy boot disk.