I just bought a little HDTV and did a scan and the only QAM channels left were audio-only channels. Even the basic channels you paid for were scrambled in the digital side, let alone extra like Leafs/Raptors/movies/internationals/etc.
It can pick up OTA NTSC and ATSC signals, regular cable (analog) and unencrypted QAM for the q version. If you have digital cable, your signal is encrypted and decoded by your Rogers box. You would have to plug the output from the cable box into the tuner.
You can use the Hauppauge HD-PVR (component) or, depending on your box, output the picture from the cable box via coax (cable, like most VCR's are commonly used), RCA (yellow/red/white) or s-video and run it through a tuner or capture dongle/card.