Joe Hill writes: “I was having trouble with the Home button not doing anything on my new iPad2 and wondered if anyone else was, too. Online I found this post on discussions.apple.com. It worked for me.
I undocked Safari from the bottom of the screen and rebooted my iPad. It instantly started working flawlessly! I ran it pushing the button often and it never missed! Single clicks, double clicks it’s been working perfectly. I tried the same thing for my iPhone which was having the same issue and it also has worked perfect ever sense undocking safari, rebooting, and then it was safe to put safari back to the original location! So far all of the clicks to the home button have worked!”