Bertros,
As long as the channel is on the same device, you can just put the channel name in the next index of the channel array going into your AI one scan VI. Your data will be an array with 2 elements, in which you are already breaking out index 0 to get the first channel; get index 1 for the second channel, etc.
Incidentally, what are you using your boolean shift register for? I see you putting values in, but you don't use it anywhere, so you don't need it.
Mark