If you're considering give Win8 a test drive, I'd suggest using a virtual machine manager like
VirtualBox. If you install VirtualBox, you can then install Win8 into a virtual machine that will run as an application within your current operating system. You won't be able to test how well its graphics drivers perform with your hardware (sorry, gamers), but other than that you'll get a good glimpse into how Win8 might or might not work for you.
You don't even need to burn a separate DVD from the .iso file. You can install Win8 from VirtualBox just by pointing at the .iso on your desktop.