Bootcamp freezes upon selection

Hello, I have a 15" late-2011 macbook pro.

For over a year now, I have been using windows 7 with bootcamp, no trouble. Last week, however, for no reason that I can figure out, Windows would not boot. More specifically, I would open the disk selection menu by holding alt, but the instant I selected the bootcamp partition, the computer simply froze indefinitely.

After searching the internet for solutions, I found nothing, and in frustration backed up my computer, wiped it, and reinstalled OS-X. I managed to get my hands on a copy of windows 8 through my school, and installed it without issue through bootcamp. Two days later... same problem. Even when I try to boot up from the windows 8 installation disk, I have the exact same problem - it just hangs at the selection menu. Selecting EFI-boot from the installation disk seems to work until I get that "your pc ran into a problem and must restart."

Is there some sort of update to os-x that may be causing this? I do not think it is a hardware problem, becasue both times, the Macintosh-HD partition has seemed to be fine. Again, I was unable to pinpoint anything that changed in the time that stopped working.