1. Closed Caption. Here's an article on that very question: http://support-us.samsung.com/cyber/popup/iframe/pop_troubleshooting_fr.jsp?idx=168311&modelname=UN55C7000WF&modelcode=UN55C7000WFXZA
2. When watching HD sources [DTV(1080i), Component (1080i, 1080p), HDMI (720p, 1080i, 1080p)], the options available from the picture size are: 16:9, 4:3, Wide Fit, Screen Fit. It's simply how it works.
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