A:Answer 1) You must have reliable internet access via wifi or via an ethernet cable, PERIOD.
2) As I understand it, you need an absolute minimum of 50bbps in "dedicated" bandwidth in order to watch hi-def TV with out buffering. EG: If you have 5 TV's on your network, you need 250mbps of bandwidth or somebody's gonna buffer, from time to time.
3) Not knowing all there is to know about your network environment I cannot give good advice. Sooooo,, you should see one of the experts at Best Buy. Gather up these data to prepare for your meeting:
Bandwidth where the router plugs into the internet
Router name and model and specs
TV model and date of manufacture for each TV,
other devices which will be on your network
physical locations of wireless router and other devices,
