The reason I ask is because I am thinking about possible configurations for my house, and one problem I have been having is video streaming performance to my
tv when someone is downloading something, particularly HD videos.
I have a spare wireless router that I could set up as just a no-internet local network to connect my
tv to my imac through the usb dongle, leaving the internet network for downloads etc.
Does anyone know if this would be possible?

I have a spare wireless router that I could set up as just a no-internet local network to connect my

Does anyone know if this would be possible?