There is a lot to chew on there and I don't have the attention span to address each point in the detail that would be necessary to cover the whole field, but here goes.
1. First, you raise an excellent point about the distinction between intent and meaning. However, I'm afraid this puts you in Scalia's camp, rather than the side you seem to think you're on. The intellectual divide when it comes to statutory interpretation can roughly be described as textualists and originalists on one side vs. purposivists/intentionalists on the other. The former oppose the use of legislative history not least because it is far more probative of what you call "ulterior intentions" than meaning, and those intentions are irrelevant for exactly the reasons you describe. It is possible for a body of 435 legislators and one president to express the same meaning. It is wildly improbable for them all to have the same intent. Originalists and textualists regard the statutory text as the source of that meaning, and the legislative history as probative of their (completely irrelevant) intent.
A good litmus test for intellectual consistency on this issue is, what do you think of Presidential signing statements? You could call those things "executive legislative history." With Congressional legislative history, Congress passes a law that says X but the statements of Congressmen saying that they intend Y are used as a justification for saying the law means Y. Presidential signing statements can do the same thing. The law says X but the President signing the law makes a statement indicating that he construes it to mean Y. Do you give the same credence to the Presidential signing statement that you give to the Congressional legislative history? There is no principled reason not to do so. Yet I have never met anyone who supports consulting legislative history who also supports giving the same credence to Presidential signing statements.
2. "It was his [Scalia's] principle that he could read the language of a contemporary law any way the dictionary allowed" -- This is not remotely true.
3. "this distinction between constitutional interpretation and the interpretation of all other laws seems to me to have no grounding" -- I agree, and I'm not aware of anyone who disagrees. Every school of interpretation I have ever encountered applies the same method to statutory and constitutional text.
4. "regardless of whether he has ever come to legal conclusions opposing his political beliefs (and I haven't seen much of that in the notorious cases)" -- Texas v. Johnson, 491 U.S. 397 (1989), is a famous example. You can also read up on his track record for protecting the rights of criminal defendants.
http://www.slate.com/articles/news_...as_often_a_friend_of_criminal_defendants.html
5. "his principles of interpretation allow him an interpretive latitude that his ostensible originalism ought not" -- This claim is virtually incomprehensible to me. Nobody will deny there is some interpretive latitude in some cases (depending on the law at issue), though in 99.9% of cases the interpretation is clear enough that even far-left judges and far-right judges don't find much to disagree on. I can not even *begin* to wrap my head around the idea, however, that originalism offers *wider* interpretive latitude than a doctrine of interpretation whose guiding principle is along the lines of "do justice according to society's evolving standards of justice."
6. "the 21st century rulings are based on ignoring the dependent clause in the sentence, whereas prior rulings believed in taking the sentence as a whole to determine its intent" -- This is incorrect both as to Heller and as to the prior rulings. Heller addressed the "well regulated Militia" clause in depth. Regardless, we can probably all agree that the Second Amendment is not a model of smart legislative drafting. The "Militia" language is plainly a statement of the *reasons* for enacting the language that follows, yet it is the only amendment in the Bill of Rights that includes such a prefatory statement of reasons and it is far from clear how such a statement should alter (if at all) the meaning of the language that follows. A law that provides "All citizens must wear blue on Fridays" imposes the same legal obligations as a law that provides "All citizens must wear blue on Fridays, blue being a pretty color and all." If you have a different view based on how dependent clauses ought to be interpreted, that's great, but once again you're following Scalia's method.