To test your ISO, you can use QEMU, an emulator that enables you to test the distro without burning it. To be honest, QEMU is sloooooooow. It would probably be quicker to burn the ISO file to a CD and test by booting with it, but it doesn't hurt to know how to use QEMU, and it is pretty cool.
If QEMU isn't already on your Debian-based system, you need to install it:
# apt-get install qemu
Once the program is on your system, you can test your distro with a simple command:
$ qemu -cdrom archix.iso
Booting Archix with QEMU took about 20 minutes from start to KDE (as they say in Missouri, slower than molasses running uphill in January). However, you will know for sure that your .iso is good and that your distro will boot. Time to burn that ISO to CDs and start handing them out to kids you know. It's going to be fun!