Have you changed anything in the bios, like to get windows 8.1 to boot from the pen drive if you have you need to make sure the hard drive is set up correctly.
The windows 8.1 repair disk is from the same version of windows as on the computer. ? This could be why you can't see the images, Also make sure the drive with the image is attached to a USB2 port not a usb3.
If you want to repair the error without restoring the image it maybe worth doing the next step, It has worked for me with 2 windows 8 computers with the same problem.
Start the computer from the repair disk, when it comes up to the repair options.
Select use another operating system and select windows 8.1 from the hard drive.
Windows will take a little longer to load but will come up to the login, Log into windows.
This error could be caused by,
1. Powering down without shutting down windows. Did you have a power cut before this happened.?
2 Faulty hard drive in which case the above won't work. You could check the hard drive with either HDtune or HDsentinal. Or your computer may have built in drive diagnostics.
3 That the hard drive is incorrectly set up in the bios.
