The plasma will go the way of the DoDo bird, get the LCD. You'll be fine.
Plasma is a great heat source in the winter, lousy in the summer. It gets hot in front of the screen...and must be eating power.
I have a 50" plasma and it has enough inputs for cable, satellite, roof antenna and a few playback/record devices. It has standard 2 speaker stereo.
If you can list a make and model, one of us can look at the specs and tell you what it can and can't do.