I agree with Pygo.
In Islam, everyone is born upon the fitra, it is simply society that corrupts them eventually. Fitra is not limited to worshiping one God, it is essence of all natural human nature, to be good, kind, generous, etc. Even if the fitra of worshiping one God is erased, doesn't mean the entire fitra is.
People are innately good, they have a conscience that compels them to do good and refrain from commiting evil. Most people remain that way throughout their lives, unless they're seriously corrupted. Of course, there's also the problem of what is considered "good" and what is not, which is determined almost entirely by society. As an example, some years back, the "good", normal people were those that condemned homosexuality and gay marriage; now those people are considered bad.
However, simply having good ethics and morals is not enough, since the correct intention for being a good person is not there. For a good deed to be accepted, it must be done purely for the sake of Allah, and in accordance with the sunnah of the prophet. So if someone does not acknowledge the existence of Allah in the first place, or commits shirk, all good deeds are rendered useless in the hereafter (although any nonmuslim who does good deeds will still be dealt with justly- they will either reap their reward in this world, which is the only one that concerns them, or their punishment in the afterlife made less severe.)