HDMI Black Level

[link_of_hyrule]

I'm trying to set up my display settings for my TV and am really confused.
I have sony Bluray and Samsung Plasma TV.
For my blacks...do I set the HDMI Black LEvel to NORMAL or OFF?? I have read many threads and keep hearing different things.
Also, when playing Bluray...I cannot change this setting. UNLESS I change the video output on my player as XvYCC or something like that - this is the default setting.

But other 2 options are RGB full, RGB partial.

Please can somebody tell me which is the most appropriate setting??