Yeah it'll definitely help. Just back up to Google or Samsung in the Backup & Reset menu and you won't lose WiFi passwords, etc.
First off though try a cache partition wipe. It's like a mini reset without resetting anything on the phone but can clear glitches built up over time.
https://www.androidpit.com/how-to-clear-galaxy-s5-cache
Worth doing and giving a couple of days before doing a full reset.