Hello, since your bookmarks and passwords are stored in your profile, which is not deleted when uninstalling, you can safely reinstall Firefox without losing anything.

so I uninstall from add/remove programs then reinstall Firefox and it automatically is back to same proile with original bookmarks and passwords? Because I can not currently open Firefox

Yes same profile.

I uninstalled and reinstalled, Firefox comes up with "this is embarrasing" with some reset and refreshh buttons and then crashes."

Click start new session.