Visual Studio 2017 Reset Settings
For a easy restoring of your settings, export your correct settings with Tools-> Import/Export Settings. Save this file on all your devices and when something changed import the settings from this file. The change of your settings could have happen because VS thought your new installation is your main installation with your prefered settings. I work on 3 different devices and never recognised a settings change.
For a complete reset, go to tools->Import/Export Settings. There is the option for a complete wipe off all your settings. If your not sure, in the next dialog, there's a option for saveing your current settings, in case you want them back. Next you can choose the new default setting.