My home button almost entirely quit working on my Iphone 4. I had to push it sometimes 10 or more times to get a response.
I removed the pentalobe screws with the Ifixit Liberation Kit very easily. Before attempting the tedious task of tearing the whole phone apart to replace the home button, I tried two pieces of advice I read on the internet first. I removed the back cover only and blew out the dust near the location of the home button with a can of clean air. I also cut a thin piece of plastic coated paper (about the thickness of a business card) and placed it over the area where the home button is located. This is to decrease the amount of pressure necessary for the contacts to meet. Replaced the cover, replaced the pentalobe screws with the phillips screws provided (in case I need to open back up) and "waa-lah" it works just like brand new. My fingers are crossed - we'll see how long this lasts.
Give this a shot first before you tackle removing the ump-teen miniscule screws and other parts. It was a simple fix.