Hank,
I used the RCA connections to feed the sound from the LCD TV we have into the Coby DVD/Surround System. This is the only way that the DVD Player will work... by being connected with a Video feed as well as Right and Left Speaker leads.
Because of a fair size collection of VCR tapes... I also figured out a way to connect a VCR Player to the TV... using again the RCA connections. Where I had problems was connecting two Video feeds into one connection on the rear of the TV.
I was able to find a splitter connection... taking the two Video RCA connections, one from the Coby DVD, the other from the VCR Player, behind the TV I plugged in this splitter into the "S-Video" connection.
You should only need the three cable RCA extension cord to take the Sound and Video from the Coby DVD/Surround Sound System to the back of your TV. They are color coded so just plug in the correct colors into the proper ports on the TV. Magic !!