There's a value kit that's cheaper but it's fine either way.
You should just be able to plug everything in and the first thing it will do is boot to the "NOOBS" installer which will ask you what you want to install.
Just install "RASPBIAN JESSIE WITH PIXEL" ("with" Pixel is the graphical interface, like windows, which means you're not forced to use the terminal)
Regardless, when it comes to installing PiHole (
https://pi-hole.net/) it's actually easiest just to use the terminal
Anyway, the one complication with this entire process (even with Wireshark) is that you need to make all your network traffic go via Pi-Hole.
In an ideal world, with a more advanced router, you'd set up your router to use Pi-Hole as a DNS server - simply changing one setting.
The disadvantage with the BT router is that doing this isn't possible. As such, the workaround is to use Pi-Hole as your DHCP server, which will automatically use Pi-Hole as your DNS server.
When you've got the house to yourself (because doing this will likely break the internet for everyone while you work on it) you want to make sure Pi-Hole is setup and running with the DHCP server capability enabled in the settings.
Then, you want to disable the DHCP server on your BT Homehub and restart everything on your network. DHCP works by the fact that when a device connects to the network it broadcasts looking for an IP provider. So when you're devices reconnect and try to get an IP the BT Homehub will not do anything, but the Pi-Hole will.
Typical problems you'll encounter will be that when you do connect to the Pi-Hole and get an IP address (192.168.blah.blah) you won't be able to access the internet.
Make sure you've setup the default gateway for the Pi-Hole server to be the IP address of your BT Homehub (typically 192.168.1.254 or 192.168.1.1 - whatever you use to access the admin settings)
Good idea to keep a phone handy with internet access should you need to Google help when you're internet isn't working!
EDIT: Oh, in fact, a good way to test the Pi-Hole server is working is to set up your own computer with manual IP configuration.
With the Pi-Hole DHCP turned on, set up your default IP to be one within the DHCP range, subnet mask to match and change the default gateway to be the IP address of the Pi-Hole. Set the DNS to be the same IP address as Pi-Hole as well.
EDIT2!: Something else worth knowing - because Pi-Hole just blocks access to adverts, some text based adverts can still appear in your browsers. Clicking on the links obviously results in blocked pages which can be annoying for some (an example of this might be clicking on the adverts at the top of google search results) as such, I'd highly recommend adding an advert blocker to your browsers on the family computers which removes/hides the physical elements from the web pages so that they can't even be accidentally clicked.