Bootcamp won't recognize discs or USB

I'm trying to install Windows 8.1 on my 27" Mid-2011 iMac with Mavericks and no matter what I do it doesn't work. Bootcamp cannot see any of the bootable media I throw at it. I bought Windows 8.1 from Microsoft (full version) and made a bootable USB and burned a DVD from my other Windows machine. When I try to go through boot camp it never recognizes anything. I even moved the .iso over to the mac and burned a DVD off the mac and it still doesn't see anything. My bootcamp doesn't seem to have an option to create bootable media like I see in a lot of walkthroughs. I've also tried to create my own partition in Disk Utility and boot to the DVD manually but it hangs at the black screen with the Windows logo. Any suggestions?!