Modern HT systems support DTS or Dolby Digital 5.1 or 7.1 audio. These systems want a center dialog speaker by the TV, two rear speakers, two front speaker, two (optional side speakers) and a low frequency (the point 1 part in 5.1) speaker. Your DVD player, cable box or satellite receiver need to have a coaxial digital or optical digital output that you run into your receiver. Your HT receiver will support these inputs as well as the built in DTS or DD decoder. Make sure you get good speakers. Running wires really can't be avoided. Most local home theater stores have pros that will run the wires, if you're not up to it. The audio from a well done HT system is amazing.

Okay, everything you wrote is Greek to me! I'll try to keep up & understand.

We have an older TV that needs a "splitter" box to connect all the new-fangled equipment, to & from it, so the HT system, etc., would have to plug into that.

The system we have now hubby bought at an estate auction & it's missing the AM/FM antenna that can't be purchased anywhere. I contacted Sony, looked at Radio Shack... So I can't listen to stereo. It's missing a bunch of brackets to mount the speakers on the walls & I tried locating them as well. And not too long ago it started not giving us any sound when we try playing a DVD. I haven't tried a CD.

Time to "cut and run."

Sounds like you need to start from scratch. You could start looking at the consumer electronics stores like Circuit City or whatever you have in your neck of the woods. Figure out what fits your budget and needs and spend some time playing with it in the store.