Can't install Windows 8?
The Bootcamp app will walk you through creating the install media from your ISO and the proper partitioning. No need to create one manually.

I would delete that partition you made, expand your Mac volume back into the open space and then recreate the USB stick using BootCamp. It should ask for an ISO of the Windows install media and use the drivers in the App to slipstream the driver files into the installation media. You'll need a 4GB USB stick (minimum, bigger is fine). Creating the install USB stick takes a while (30-40 minutes in some cases) then run bootcamp and follow the prompts.

It will give you a GUI for resizing your Mac partition. It will then properly format it and put the necessary Windows boot files on the drive and then boot you into the Windows installer.

If you follow those instructions it should all work for you fine, unless there is already a non-standard partition arrangement on the drive.