I've been using Linux for what seems like forever. Over the years, I've noticed that I use the command line less and less, because the GUIs have just gotten so much better. Even still, there are ...
But both are worth considering.
Create the ultimate OS for your home lab.
Linux is highly secure, but you should still have a firewall. You should know if your ISP's hardware (gateway) uses a firewall. One of the easiest Linux firewalls is UFW and its GUI sidekick, GUFW.