Biggest Question of all in Harry Potter: Why did Voldemort want to kill the Potters?

There was a prophecy referring to a child born at the end of July, with parents who had 'thrice denied him'. Voldie supposed it referred to Harry, rather than Neville - the only other one who could have fit it. The prophecy basically said that Harry would kill him, and he feared death more than anything else, so he tried to kill Harry. And Lily/James were just collateral damage.