Changing from U-Voice to VoIP

I've dropped Uverse Voice and I'm now using an internet voice provider like MajicJack.  I would like to connect this VoIP service to my house wiring so I can connect phones to the wired jacks like I was using with Uverse Voice.  I have a 2wire gateway model 3800HGV-B.  On the back of the gateway there is a "Phone Line" connection and "Phones Lines 1 & 2" connection, both connecting to a single cable coming thru the floor.  The "Phone Line" connection is connected to the Green/White-Green pair of wires and the "Phones Lines 1 & 2" is connected to the Blue/White-Blue pair of wires.  I have disconnected cable from the "Phones Lines 1 & 2" connector on the back of the gateway and the internet and TV are still working.  I assume the Blue/White-Blue pair is connected to the wired phone jacks in my house and the "Green/White-Green" is connected to the box on the outside of my home to carry Uverse service to the gateway.  

My question is, Can I just disconnect the cable connected to the "Phones Lines 1 & 2" jack on the back of the Gateway and move it to the VoIP box phone line connection?

Will disconnecting the cable from the "Phones Lines 1 & 2" jack on the back of the Gateway isolate the Uverse wiring from the phone jacks in my house?

Thank you.