[Please help] How do I boot an iso image?

Hey,
I would like to install something which came in a .iso format, could you please tell me what to do in order for me to book straight into it, because that's what's needed to install, a bit like the install disks, would I just hold C like I do to boot the Mac OS X discs, or something else?

I hope for a prompt reply as I have to have it installed by Sunday.

Many Thanks,

Mambo, a new user. :ninja:

youd have to burn it in toast, then insert it, then boot from it.