This is the line that I pay attention to in that House stream you posted:

Stream #0:2[0x1b]: Video: h264 (High), yuv420p(tv, bt709, top first), 1920x1080 [SAR 1:1 DAR 16:9], 29.97 fps, 59.94 tbr, 10000k tbn, 59.94 tbc

The h264 is the standard that Handbrake works with, and the 1920x1080 says it is a full screen image. If you web optimize or do other things to reduce the file size it comes out for a smaller screen or for a YouTube screen.