If your thinking wood, wood absorbs and stores heat. Horrible material to use when building anything electronic or mechanical. Plastic does the same, and many other materials I can name. Personally, I prefer a good 'ole metal computer case.
My motto is "If the case doesn't make you wonder if your foot is broken when dropped on your foot, its not a proper computer case!". I hate flimsy computer cases, HATE them, almost as much as I hate sharp edged computer cases like the old Packard Bell Legends, mind you, my first computer was a Packard Bell Legend, no clue what the model was. It was a piece of junk though, I can remember what it looked like, but I can't remember the model, I believe it was a 50MHz PMMX, though I am unsure.