Lots to consider here.
#1-Maybe post a link so we can actually see what this "channel 24" desk is as I have never heard of it.
#2-a 192 IO will not work in any way with an Mbox, OR with Pro Tools LE(the 192 will only function with HD/HDN/HDX card and HD software, or a Waves StudioGrid(not positive on their exact hardware) that has a Digilink connection(which would also require Pro Tools 9 or newer)
#3-Beyond that, if its a typical mixing console, it really serves no purpose in a modest DAW setup that only has 2 ins and outs. I run 48 ins and 32 outputs in my commercial studio with no console at all
#4-is it possible you are referring to a CONTROL 24? That is a control surface that does work with Pro Tools LE. It connects via an ethernet connection and needs to be set up under the peripherals menu.