Hey Stainless,
I have a similar setup using the same motherboard.
I too was having the same issues you explain with blue colors using the component cables. I eventually gave up and went to s-video and all was well.
Just recently things were working all to well on the HTPC so I decided to revisit the component cable issue. Fortunately the newest nvidia drivers
http://www.nvidia.com/object/winxp_2k_93.71.html
ForceWare Release 90 Version: 93.71 seem to do the trick. I'm not sure what drivers you are using, are they from ASUS?
Now that I have my system running on the component cables I may switch back as the overscan is horrid, and as far as I know there is no way to adjust that unless you are using either s-video or composite cables.
Also one more note: I had to have my svideo cable plugged into the video out bracket at the same time as the component or the system would not find the component cables as an option. Found that out by being lazy and not unplugging the svideo
Thanks