In order to be protectable under copyright law, a work must be original, creative, and fixed in a tangible form.
It must be an original work, and fixed in a tangible form of expression.
Under US laws, all copyright claims under federal copyright must be made in US district court. You would sue for a declaratory judgment that the work did not meet the federal criteria for an enforceable copyright, once you have standing to sue (i.e., someone has threatened to sue you for copyright infringement of an invalid copyright).
No; formal registration is not required for protection.
In Canada software is protected as a literary work under the Copyright Act of Canada. Copyright is acquired automatically when an original work is generated, the creator is not required to register or mark the work with the copyright symbol in order to be protected.
The copyright lasped on the death of David Selznick, but later it was renewed in the USA. It will remain under copyright there until 2045.
Drugs and other pharmaceuticals are protected under the patent laws not under the copyright laws.
Trademark yes copyright no.
Yes. All aspects of the film are still under copyright.
You need permission from the copyright holder or an exemption in the law.
A website is considered a "literary work" under copyright law.
Yes, if you have a copyright in any country covered under a multi-lateral treaty, such as the USA under the Berne Convention, your copyright must be honored and protected by the laws of the other 160 countries under that Convention.
Not particularly strict; it's under the same copyright laws as anything else.