Vivid,
Video 5,6,7 is reserved for Component/DVI - HDTV/DVD input with Video 5 and 6 being component and input 7 being DVI.
BTW: Page 39 of Manual, "Component video connections is necessary to view 480i,480p,720p and 1080i formats."
That limits you to Video 5,6,7 (I think) because right below that it says "You may also use the S Video or composite video connections, however, component video (Y,Pb,Pr) will provide the best picture quality for all formant types."
One last note from manual. "Advanced Video is unavailable when you have selected mild picture mode, or you are watching 1080i, 720p and 480p sources with video 5 to 7 inputs"
Advanced video = DRC Mode- High Density, Progresive, Cinemotion (reverse 3/2 pulldown) and BN Smoother.
Good luck