nuwanda, I looked at your example photo, Now maybe this was not a good example. I see there is some quality loss BUT for YouTube it's not bad. Maybe you are expecting to much. YouTube takes what ever you upload and then downgrades it to make it playable in a quick way.

It turns it into an .flv file a kind of flash file. Look at the file size that you are uploading and compare that with the file size of the YouTube Video. This I think is the problem. Not your settings when rendering but what YouTube is doing with it once you have uploaded it.

One other thing, when you first upload a Video to YouTube it takes a while before their severs finish the final quality so give it a couple of hours after uploading before you measure the quality.

I hope this helps you come to terms with your problem.

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Every thing said by me should be taken with a pinch of salt. Unless you have high blood pressure, then I would recommend a salt substitute.

Have you tried rendering in mp4 with the max settings?
If an uploaded video is HD, YouTube converts it to an mp4 file as it is small and can be easily streamed whilst maintaining most of it's quality.