Look on your desktop. Do you see a folder called; Old Firefox?

https://support.mozilla.org/en-US/kb/recovering-important-data-from-an-old-profile

https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

Separate Issue; Your System Details shows;

Installed Plug-ins

Adobe Shockwave for Director Netscape plug-in, version 12.2.4.194 Adobe Shockwave for Director Netscape plug-in, version 12.2.3.183
Having more than one version of a program may cause issues. You must remove the older programs. Then get the current full installer.

Shockwave Director: Shockwave Standalone Installer / Uninstaller{web link} Shockwave Director Version Version 12.2.4.194 http://get.adobe.com/shockwave/

These can't get your data back, but will help in the future.

These add-ons can be a great help by backing up and restoring Firefox

FEBE (Firefox Environment Backup Extension) {web link} FEBE allows you to quickly and easily backup your Firefox extensions, history, passwords, and more. In fact, it goes beyond just backing up -- It will actually rebuild your saved files individually into installable .xpi files. It will also make backups of files that you choose.

OPIE {web link} Import/Export extension preferences

Febe was installed...folder empty. Everything related to Firefox is gone. Firefox bookmarks toolbar has sites from IE favorites bar but nothing from Firefox.

You can export the IE bookmarks to restore those. But as to your Firefox data, unless you have a backup somewhere . . . . . . .

Firefox has been default browser for years and had valuable bookmarks; several business related. Is there a solution to restore what's been lost? Can I ever trust Firefox again?

I've called the big guys to help you. Good luck.