Answers: you burn a bootable iso to it
If the iso is bootable, later the disc will be bootable
You probably lately necessitate to configure your bios to boot from cd as first priority, otherwise, it'll freshly boot from the complex drive
Or you can try and see if you enjoy better luck beside this:
ftp://terabyteunlimited.com/burncdcc.zip
It's free iso burning software and burns bootable cds no problem
BartPE
http://www.nu2.nu/pebuilder/