Just a couple of clarifications:
1 - Batman believed Joe Chill (a common thug) killed his parents. Chill was killed by a supervillain during Batman: Year Two (by Todd MacFarlane). But later Bats found out Chill (although he was a killer) wasn't the man who killed his father. So Bruce's neverending crusade is not resolved. He now strikes at the whole criminal community, turning it into the embodiment of the man who killed his parents.
2 - John Byrne explained that Clark hunches forward a bit, combs his hair back, wear deep-lensed glasses and speaks in a much softer tone than Superman. The result is a completely different visual, like Robert de Niro usually do in his movies. Add to that the fact that no one thinks that Supes has a secret id, and the illusion is cast. during the Byrne run, Supes used a trick that Jay Garrick (Flash I) came up with, and constantly blurred his face to avoid photographs, so no one knew the exact details of his face.
3 - Yes, the movie Batman is a sucker for a blonde. I mean, all blondes in the movies were told his ID. The comics Batman takes this much more seriously, to the point that he hypnotized himself so that, if confronted by undeniable evidence that Batman in Bruce Wayne, he'd split his mind, and be Bruce Wayne until he heard the key phrase (which was Dick Grayson's oath as Robin: Never to sway from the path of justice...).
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