Safe Mode temporarily disables any 3rd party app you installed, so if the problems are due to one of those apps, they should go away in Safe Mode. It helps you narrow the problem down. Here's the text from that site:
[h=4]Turn on safe mode[/h]
- Turn the device off.
- Press and hold the Power key.
- When 'Samsung Galaxy Note5' appears on the screen, release the Power key.
- Immediately after releasing the Power key, press and hold the Volume down key.
- Continue to hold the Volume down key until the device finishes restarting.
- Safe mode will display in the bottom left corner of the screen.
- Release the Volume down key when you see Safe Mode.
[h=4]Uninstall third party applications[/h]
- From any Home screen, tap the Apps icon.
- Tap Settings.
- Scroll to 'Device,' then tap Applications.
- Tap Application manager.
- Swipe right to the DOWNLOADED screen.
- Tap the desired application
- Tap Uninstall.
- Tap Uninstall again to confirm.
[h=3]Turn off safe mode[/h]
- Press and hold the Power key.
- Tap Restart.