Cant get dvd to work. my kids were messing with the tv to set up wi, now i cant get the hdtv

Question

my kids were messing with the tv to set up wi, now i cant get the hdtv connect to the dvd to work, as the device for this connection does not show. i have also tried to connect with other cables into the input 1 or 2 (input two device option on the device menu has also dissapeared) still no luck. so many varialbles, kind of lost. thank for you help. i tried to change channels and change input conectors and plug in options from both the back of the dvd and the tv