I'm sure others have posted better ideas, but I used to run a dual wifi setup at my old house. One router was the 'main' one and was basically just the core internet access, connecting to the second router. The second router had my VPN setup in the firmware, so if I wanted to pirate games/movies or do other VPN stuff, I just had to swap from one wifi to the other.
We needed the non-vpn network so that mom could do her job (work-from-home, they didn't like you using a VPN that wasn't their in-house connection).