I did use a s-video connection for all captures (NTSC). I noticed a definite improvement in color vibrancy and contrast. I was hoping the Zelda screenshot would be a good reference. By Hi8 broadcast decks, do you mean just the vcr's that were only sold in Japan? I've seen them on Ebay. Do they have an "Edit" function like the camcorders did. It reduced generation loss when copying to vhs. When capturing, it reduced color bleeding and haloing.
What is DScaler software? Do you think most computer stores would know how to help set something up with all these things ready to go?
Composite capture. (Ignore the tracking line)

http://www.uploadfile.info/uploads/c03862b379.jpg