A closeup pic would help.
It looks like blocking installed between the joists and the wall below is non load bearing. But, you'd have to confirm this by looking at what's above the joists on the next floor above. If there's a wall or posts on the same spot, then it's carrying some load and will need to be header'ed out with double and jack studs/etc on either side of the new opening.
You can triangulate the location and transfer to the floor above to find if there's weight on this wall or not.
more pics of the metal beam you describe would help.
A bit confused by the early pics. Is that above that basement wall?
Then the blocking between joists is making a chaise for the hvac ducting. Is that so?