Decreased video quality when put on disk

[Whitewash 0]

My setup is a Mac with EyeTV Diversity tuner (firmware 102.17) and software version 3.6.9. This all works fine and I get good quality video on my 27" screen as programmes are screening or on playback. The problem is when I try to transfer recordings to disk. I use Toast Titanium and just drag the recording file directly from EyeTV onto the Toast window. Often the resulting disks show pixellation and fuzziness, especially round the edges of moving objects. This is a significant deterioration from the original recording and I hope there is some way of matching the disk version up to the original.

Maybe this is the wrong forum to ask this and maybe I should enquire in the Roxio forum as it may be that the encoding settings are not optimal but I thought this might be a good starting point. I've never been sure of the pros and cons of the different export formats and, if I just drag the file across, which one will be used.

Any advice gratefully received.