There are four screws you need to remove. You can see two already. The other two are hidden underneath a panel that pops off. The panel has tons of holes in it, and underneath you can see some metal.

Insert a screwdriver into the bottom of the panel. There is a small rectangular hole. Pry off the panel.

Now, you will see four screws. You only need to take off two of them. I believe they are the two outer screws.

Once you are done with all of that now you are ready to take off the bottom. The rear part of the bottom (opposite the screen) comes off easily. The side next to the screen is harder. Pull away the bottom plastic as if it were hinged on the side with the screen. You may hear a noise like plastic breaking but no plastic is really breaking.

Then there is the metal shield. It has about six screws holding it down. Remove all the screws and pull off the shield.

Now you want to remove the metal cage that has the hard drive and CD drive. Remove the wires from the HD and CD and remove the four screws holding the cage to the metal plate. The cage will then lift off.