I am having the same problem with a 15" MACBOOK PRO... have tried almost every install disc I can beg borrow and steal... but squat. Am looking at bidding on the same disc as you yourself have used to reboot.
This is a crazy little quirk and I am not happy with the situation, especially as Apple have a TERRIBLE habit of not even considering looking at a machine that is out of 'applecare' and as I am the 2nd owner I am considered more of a plague than anything else... like a human with feelings... or emotion... or the need to USE A BLOODY COMPUTER : (