How can i boot from CD first?

I have a Asus F3sv-A1, and i like broke the harddrive. :[
It tells me to insert a os/recovery cd and restart it. But it returns to the same screen because it reads from the harddrive first rather than the optical drive How can i change the settings so that it runs from the CD?

I have Vista Premium

 

When the boot screen first appears, launch your boot menu (probably by pressing F2, F8, F12 or something) and choose what to boot from.

 

On my F3Jp, you press ESC to access the boot menu.

 

C90S is also the ESC key to choose boot option.

 

When i want to boot from something other than my hard drive, i keep pressing ESC on start-up and then it gives a list of devices to boot from, you then just go to your CD/DVD drive and it will boot from that.... if the disk IS bootable

 

To check if the disk is bootable enter BIOS by pressing F2 and select CD as 1st boot device, disable the rest. If the computer does not boot then the disk is not bootable.

But a recovery disk should be bootable.

If you did BREAK your hdd physically don't expect good results out of the recovery though. If you only broke Windows, then it's indeed a good solution Back up your data first, though.