We are thinking about getting a Samsung 120Hz TV and a LG 60Hz DVD Player, but would they work together since they are different Hz? Or would the TV downgrade to 60 Hz?
The TV is a Smart TV so do you need a special DVD player to access that feature?

http://www.lg.com/us/tv-audio-video/home-theater-systems/LG-LHB306.jsp

http://www.samsung.com/us/video/tvs/UN55C6900VFXZA

The sound system does come with a DVD player, right?

Also, do you need a special HDMI cord for the two? Are there different speeds.