A:Answer I am running both of these as an example, so you can decide.
If you are in the apple world (iPhone, iPad, iTunes account), get a Apple tv. it plugs in via the HDMI and has apps that let you run netflix, youtube, hulu, etc.
If you are looking for something that does that, but doesn't need to be Apple, go with a Roku 3. Same concept, but does offer a wider range of 'channels'. That is, content sources.