The vertical (fuzzy) blue line appears on the left of 4:3 content, can't get rid of it with screen adjustment, unless you like zoom or stretch mode. I think it's a bad conversion to digital that causes that line to be there.
Storing 1080 lines instead of 800 puts more stress on the compression algorithm, yet in quiet scenes more detail should be able to be stored to help with upscaling to 4K. Movies don't fill the entire disk anyway
http://www.avsforum.com/forum/150-b...-audio-video-specifications-thread.html?pp=60 Perhaps the 4K mastered ones are, those use higher bitrates and x.v.color. I haven't tried one of those yet, too busy playing GTS to watch movies!
It's a balancing act between resolution and bitrate. Blu-ray doesn't look that great when you pause it during heavy action, better than pausing Netflix or HDTV, yet still very much bit starved. It's probably the same for 4K UHD, however downscaling that to 1080p should provide a more stable picture with less up and down swings in resolvable detail. I wonder what's going to store video content for 8k.