Not sure if this will help but it is the shortest way of doing things instead of pulling files and going into the guts in about. So you could give this a try https://support.mozilla.org/en-US/kb/how-to-fix-preferences-wont-save as it was recommended in this support article https://support.mozilla.org/en-US/kb/how-to-fix-preferences-wont-save which as said is alot of mucking about.

If this works/or does not please let us know what happens and if it fixs the issue please mark as solved.

Miladyginger said

My search bar will only use what I have set for the default. when I click on the "change search settings" button, all the search engines I had checked before to be on the search bar list are STILL checked. so for some reason they aren't showing up in the search bar when i go to search..just the default search engine.

Do you use any add-ons or custom style rules to modify the appearance of the search bar?

Have you added a lot of extra search engine plugins to the built-in ones? I ask because one thing to try would be resetting your search settings, but you would lose your extra search engine plugins.