YPbPr to VGA (consoles on monitor)
No, that won't work. That schematic is for stripping sync-on-green from an otherwise normal VGA signal.

Despite their colors, the three RCA connectors used for component video are not green, red, and blue components! They are Y, Pb, and Pr components. (Y is luma -- brightness -- and Pb and Pr are two axes of chroma -- color.) To convert these signals to VGA, you would need to:


Perform a colorspace conversion from YPbPr to RGB, and
Extract horizontal and vertical sync signals from the input.