Router IPv6 and Pi-hole DHCP

Hi - I just want to check that I've understood correctly what to do about IPv6 before switching over to the PiHole DHCP server. This is new territory for me.
The screenshot shows the IPv6 settings in my Vodafone Ultra Hub (sorry, I don't know who the actual maker is).
First I turn off the IPv6 slider, then should I leave on or turn off the green sliders under

OK - this just answered itself. Because I don't understand what IPv6 is, nor the data flow between internet / router / DHCP server, I didn't want to risk switching off things in the router that needed to be on for the PiHole DHCP to handle IPv6 correctly. So, in a quiet moment with all the rest of the network off and only my PC on for the router's web interface, I slid to 'Off' the IPv6 slider. The router then took off the screen all the other options leaving the screenshot below.
Summary - turn off the IPv6 option and this router will turn off the rest.