1) This isn't the best forum for these sorts of answers. You should really check out HTPC forums for better answers.Originally Posted by judoGTI
2) I don't know about any HTPC or PVR card solution, but my TiVo (which has the same functionality that you're looking for) came with a cable that connects to a port on the back of my digital cable box. The TiVo sends the signal to change channels through that cable. It doesn't support all digital boxes, though. I guess I was fortunate in that regard. The TiVo also supplies infrared deals that function like a remote control to change the channel on your digital cable box. I would think it's likely that some method of controlling a digital cable box would have to be supplied with the PVR card or at the very least make it an available option.