Get the very last one. The pic of the huge entertainment center. If you could combine all of that into one huge cage by knocking out some walls and such, then you would have so much horizontal AND vertical room that your chameleon will probably throw a party in there it will be so happy. The flip-out doors on the bottom would be great to throw a drainage system of some sort under there, hidden from view. The cage itself within the cabinet is already off the ground a bit, so that is good too.
You could really make any of these work... In my opinion though, the first one, being angled towards the back like a triangle, minimizes room in the cage. Sure that one is 33" wide but coming to a triangle-point near the back means that near the back, it's no longer 33" wide and instead is much slimmer. The second pic, with the two shelves and three drawers, looks a little small... But that's just because I can't guess size and it doesn't say. Lots you could do with that one though. The third pic, of the TV stand for a 40" ... That lacks vertical height. You want lots of vertical room, as chameleons like you climb.
That last one though... That 3 piece..... You could do SOOOOOOOOOO much with that if you had some time to put into it. You could create a masterpiece.