Back seat removal of a 2006 cobalt coupe

the following quote is taken from the web site from a chevy cobalt forum. if you have any more questions they might be able to help you directly.
(all it is is 2 bolts. Just take off your door panel and pull back the protective plastic and look for 2 bolts that line up with the door handle.)

How Do You Replace The Outside Door Handle Chevy Cobalt Forum Cobalt...

This is going to sound a little odd, but properly jack the car and then try opening this door. Put the jack in the recommended jacking spot on the passenger side.

Imagine that the back and front ends of the car are compressing the center of the car. By lifting one end or the other, the center may shift. Otherwise you do not have a frame, but the engine cradle may have a support located closer to the center of the vehicle. Do not jack the sheet metal, but you may catch the cradle and apply lift there.

You may notice by putting in a piece of cardboard in the doorjam on whether there is an increasing gap as you jack the car.

You can probably access the light from the trunk.
1) Remove the two screws revealed when the trunk lid is opened.
2) Unscrew upper cargo net anchor,you will see 3 or 4 wing nuts.
3) Pull back carpet wall, remove nut on threaded rod.

Have you tried shifting the gears completely through and then putting the car in park. It sounds like the car isn't able to be put completely in park to release the key. Try putting the car in N and removing the key. Even thought the car may not completely be in park to release the key, The gear most likely is in park but not enough to make the switch/sensor to release.

If the wheel is turned in either direction, pull the whell in that direction and try getting the key out. If that doesn't do it, try shifting the automatic transmission from Park back to drive, and then to park again to disengage the interlock.

this may be a compresor issue,when the car is normal(a/c off) the compressor is not draging the engine,how ever when on if the compressor is goin bad(seizing) will turn your engine off and the belt will drag. have you compressor checked and also see if the system is over charged.

Hold down the clock button for at least five seconds then release the button. You should see a new menu on the screen to set your clock.

in trunk under back window

(The engineers couldn't have hid these much better if they tried...)

1) Open the trunk lid all the way.
2) Look up under the inside top edge of the trunk opening.
3) You will see two 1" wide x 1/2" thick, black plastic knobs, about 1' apart from each other.
4) Pull straight back on a knob to release one of the back seat halves.
5) Go forward to the back seat compartment and lay each released seat the rest of the way down.
6) Paint the buttons white so the next person can find them easier!