I have not really considered breached into the hardware capturing alternatives until I got Sky+ (a uk thing like tibo?) which records to an internal hard-disk.
I have tried finding out how it works but as you can imagine the makers are not likely to give blueprints

The quality/sharpness of playback from this specific device is the same as the broadcast quality, superb. However, once captured to avi and then converted to mpeg(1) the quality is not as good.
I have downloaded mpeg2 svcd files and the quality is basically dvd!?

I guess my main question is, would it be ever possible for me to capture standard digital tv to such a quality as the svcd files? (no HDTV in the uk)