Living room Makeover

Years ago first hubby and I put up some really dark paneling. Then years later we had a bad roof leak and part of the ceiling caved in. First hubby's solution was to nail the wrecked ceiling back in place and cover the nightmare with ceiling tiles. Unfortunately the tiles in the corner began to sag some years ago, so to prevent them from caving in, I had to brace them in place. Since hubby #1 didn't seem to care to fix it, everything stayed. The ceiling ties were shabby and not even straight. The old, dark paneling was a mess. Fast forward to present.
BEFORE:

The east end

 The west end with a computer desk and falling tiles

THE DEMOLITION BEGINS:

The east end, or front of the house

The west end showing the ceiling and the damage. Removing the paneling also uncovered mold, which I am cleaning. I have always had allergy problems when sitting at that corner desk. Is it any wonder?

Close-up of the damaged ceiling

I am so thankful my new hubby is so pro-active and non-judgmental regarding my living situation. We are going to hang new wallboard (sheetrock) over the existing walls. We are thinking the damaged ceiling needs to be replaced. We aren't sure how to proceed because we can't decide....should we remove all the boards or put new tiles up? The boards are not going to support heavy sheetrock.