I've had my computer hooked up to my stereo and TV for awhile now and there has always been a problem with the video that I attributed to the long cable run from my comp to TV. Kind of vertcal distortion in the picture, rather subtle, but still noticeable and irritating. Anyway, last night I was watching some Star Trek the Next Gen that I had recorded earlier with my tuner card and I noticed the video was "letterboxed" a bit on all four sides. I thought it was a problem with my video card [MSI Ti 4200] so I went into the video settings to try and correct the problem. I was unable to find a fix. And with good reason, the reason it was "letterboxed" like that was because the tuner card had recorded it that way for some reason. I'm not sure if it's just a quirk of that channel [Spike] or if I need to adjust something in my capture software.

Later I tried watching some video from my comp >> TV but the screen on my TV remained black. Yet there was a picture displayed on my PC. I'm using the "clone" option on my video card to drive both displays. This was at fullscreen. When I restored the video to a windowed display, my desktop was displayed on my TV, but the video window remained black on TV, fine on computer! Weird. Eventually found the problem on this screen:
Display Properties>Settings>Advanced>GeForce Ti 4200>Full Screen Video
I had set "Full Screen Device" to disabled. After resetting it to "Secondary Device", I was able to view video on my TV again. But a couple things were different.

One: I can keep the video in a window on my comp and it will be displayed in fullscreen on my TV. Way cool, I don't have to change resolution to watch video on my TV anymore! And I still get to see my desktop fine when video isn't running or doesn't have focus.

Two: even better, no more vertical line distortion! I guess it wasn't my long cables after all, just the way my video card was driving the secondary display. Yowsa!