Natively, the BBB file has only one purpose, to be used as the source of restore to a BB. It is in a proprietary format, and BlackBerry provides no tools to use it for any other purpose.
But, there are 3rd party PC apps that can parse it and present it in human readable format...a few minutes with Google and I'm sure you will find one that will work for you (and likely for free!).
Occam's Razor nearly always applies when troubleshooting technology issues!
If anyone has been helpful to you, please show your appreciation by clicking the button inside of their post. Please click here and read, along with the threads to which it links, for helpful information to guide you as you proceed. I always recommend that you treat your BlackBerry like any other computing device, including using a regular backup schedule...click here for an article with instructions.