Inspiron 15 3521 crashed; can't do back up

I recently did a Windows 8 update and when the laptop rebooted, it said error and there was a BCD missing message.  I used my USB flash drive with the Windows 8 recovery on it to get to the Dell Troubleshoot page (this was after I had to switch from UEFI to Legacy mode).  I began the Dell Datasafe Emergency Back up & Recovery.  The only options it gave me was to restore to factory settings so I clicked that and then it asked if I wanted to back up my personal files.  I clicked yes.  Now is when the problems start.  It tells me what files it chose to allow me to back up with an option to "show more".  When I click on "show more", it times out after 2 minutes and brings me back to the home page.  I bought a brand new USB external hard drive today and, instead of clicking "show more", I clicked next.  It then told me to plug in my external hard drive.  I did so and clicked next.  The next message I received is that there is no USB attached or the drive is not recognized.    I was on the phone with Dell last night for 2 hours (and 7 call transfers later) for them to tell me they can talk me through it for $130.00.  I am not sure why the USB is not being recognized since my flash drive is working in one of the USB ports.  I do not need help reinstalling the Windows 8 OS - I need help saving my files before I do so.  Can someone please help me?!?!  All of my 1 year old daughter's pictures are on this computer and I would be devastated if I lost them! :emotion-9: