My home button seems to be working okay to move out of apps etc, and double tapping brings up the expected menu, but on the home page, a single tap no longer swaps to the search interface, and when modifying app positions, clicking home no longer stops the apps 'shaking' - is there any way to rectify this?
These features should definitely work with the home button on your 4S. You should contact Apple to get a solution, which may include repairing or replacing the phone. If you are near an Apple retail store, set up a genius bar reservation. If not, call Apple for support.