It dosnt matter what setting for streaming video etc as the quality is dependant upon the quality of the actual clip, what it was encdoed at.
You could put all settings to max = All sliders to the right.
Even watching DVD you will not notice a difference althought the quality will be 100 times more than a streamed clip.
Theres nothing you can do to improve the quality apart from getting a higher quality video clip.
For example (Generally speaking)
A clip that is 10MB and 20 seconds long would be be higer quality than 2MB at 20 seconds. You owuld notice a difference in the playback.
All you can do is just leave it or recieve higher quality streams etc.