Connect your analog cables into the input of the Canopus 300. Then connect the Canopus to your computer with Firewire. In your setup, Choose Format:NTSC (or PAL) and Use: DV NTSC or DV NTSC Firewire Basic (or the PAL versions in you’re in PAL land). You should be good to go.
I guess I should have asked if you have firewire first but I assume you do.
This method does work as I have used it a lot for analog captures.
Cheers,
Mike