shoot neutral - spoil in it in post
Rule of thumb whichever the medium:
1-shoot neutral (mid exposure, accurate white balance, 50 shutter speed...);
forget "film looks" in camera. Avoid any P mode that it's not truly P at full quality.
2-Spoil things in post
Video will never be film no matter how you shoot. But if your original material follows rule 1 you will have a much wider range of posibilities to achive a filmish look in post.
This is like saying that if you decide to grade a shot on camera, you'd better not change your mind about the style, cause that will be it forever. It's just silly
People are obsessed with de-interlacing and I'm not too sure they know what they're doing. There are 3 methods to do it in post and only 1 keeps all the information at a considerable processing and rendering cost
Probably the best tool in post to get a film look is "Magic Bullet", especially in the hands of a professional grader or at least someone who understands photography, film and color.