Rusted lally column

We are working on our new old house. The bedroom ceiling is solid but has cracks and does not have insulation above the plaster. The third floor does have flooring and it would be difficult to pull it up to add insulation between the joists. I would like to try adding rigid insulation board to the ceiling with furring strips between that I can use for screwing on drywall. The plan is to screw the wood through the old plaster and lath onto the joists, glue the insulation to the ceiling between the furring and then screw the drywall onto the strips. Anyone done this? Problems I will encounter? Alternative ideas? Thanks for your ideas.

I'm guessing this is a curtain wall, but I wanted to get a few opinions first... This is a single story ranch home with trusses as you can probably tell from the pictures. At this time, I'm not looking to completely remove the wall, but I am looking to cutting a large opening in the wall. This way I do not have to move any electrical, thermostats, and cold air return. The trusses cover just over a 30' span. The wall isn't completely centered and it is about 3' off the beam in the basement (the wall is just to the right of the conduit on the basement picture). There is also a 3.5' span that has no beam or anything going across in between the rooms. I haven't opened any part of the wall yet to see if it has 2 2x4's at the top of the wall. From what I can see in the attic where the power goes into the wall, it looks like only one. If needed, I will consult a contractor or engineer, but I thought I would try some opinions here first. Thanks.