For DVD playback
Connect the component video output (3 RCA) + audio (2 RCA) of the HTS to the TV. This will give you better picture than using the composite video (1 RCA). If you did need to use it the component input can usually be used for composite by changing the setting in the TV menu. Check the TV manual.
For audio from the TV
Connect the optical audio output of the TV to the HTS. Check the TV manual for how to turn it on and set it to output in surround sound.