[coopns]

I downloaded Gentoo iso. How do I burn it with MacBurn for a PC?

[discotronic]

I am not familiar with MacBurn but an ISO is an ISO. It shouldn't matter what system you burn it on. It should work with a PC without having to tell the program (the one you are using to make the copy) that the disk will be used on a PC.

[Philip J. Fry]

You could use Disk Utility and burn it through there.

[mduser63]

I've burnt many x86 Linux distro ISOs on my PowerBook. Just open Disk Utility, drag the ISO into the Disk Utility window, click on it and then hit burn.