U-verse to voip

Hello,

Recently I have been thinking of switching from U-verse voice to a voip provider like Ooma. I really want to use my in-house wiring for whole-house voip, but I can't seem to find the correct answer on how to do it. I have read a lot of sites and posts. Some say I need to disconnect some wires from the NID, while others say I should already be good to go. If I do switch, I plan on porting my number and then canceling U-verse Voice.

My current setup is U-verse TV, Internet (45mbps Power) and Voice. I just want to know how to set up whole-house voip via current wiring. Any help would be much appreciated.

Thanks.