Run analog audio and video cables from the DCT to one of the receivers inputs, such as video1. If the receiver has another digital input, connect a digital cable (optical or coax) to the receiver's digital input. If you have digital cable, you will want both analog and digital audio connections - digital so you can get Dolby Digital from the set top box and analog for those channels that do not broadcast digital audio.
I'm not familiar with that receiver, but for most others you also have to tell the receiver which digital input corresponds to the video input; eg if you connect the DCT to video 1 and the audio cable to optical 1, you have to use the setup of the receiver to tell it optical 1 goes with video1.
Then just select video1 on the receiver when watching tv.
