Register the interfaces found in the OpenZeppelin file, or do I need to explicitly include the _registerInterface lines of the file in my own Smart Contract
Calling the parent does this for you. You do not need to do it yourself. Both parent and child code live in the same address. Only if you use Solidity libraries your life gets complicated.
the functions I wish to use.
Depends what you want to use them for.
If you want to interact with a token, the token interface defines the functions you are work with.
If you want to create a token then the implementation must cover each function mentioned in the interface.
Open Zeppelin is well-crafted and modular so you don't have to reinvent everything.