I'm not sure I understand what you want to do...
You could use [url="http://www.amarectv.com/english/amarectv_e.htm"]AmaRecTV[/url] It can display your input signal in Full-Screen Mode while recording it lossless/uncompressed.
I mostly capture Input from my XBOX 360 and AmaRec allowes me to capture lossless (UT Video) at 29.97 FPS, I really like that program