Interlaced scan mode: either shoot progressive or deinterlace/fieldmerge in post. Gets you a lot closer to a "filmlook"
Little dynamic range: not much you can do about it other than getting a better camera and careful lighting/exposing on set.
Clipping of highlights: the clipping into white looks much harsher with cheap video cameras (even with many expensive ones) than with film. Try adding a subtle glow to just your highlights.
Depth of field. Most video cameras have small sensors which results in a huge DOF which makes everything look a bit flat and less 3 dimensional. Once again this is more true when comparing to 35mm than lets say 8 or even 16mm film. Either shot with cameras featuring a 35mm sized sensor or use an adaptor.This has a huge impact on what you call "filmlook"
Grain/dirt/scratches. Try adding in post but I'd be very careful most of the times those plugins seem to generate a rather generic dirt look. you might scan in some old photos / films and do a bit of manual work extracting the dirt but I've seen much more convincing examples done that way.
Pin registration: Only a very subtle effect but film slightly moves within the camera, thats why most of the time when comping elements into film, I feel like I need to track even when camera was locked off. You could track some locked off filmfootage and apply to your video or use some noise functions.
Generally gamma/contrast: try to increase contrast in the dark part (while increasing gain there too). Depending on which video you shot with you might also go for less color saturation.
As far as video, ideally you would
~ use good filmic lighting, ~ control the dynamic range of the scene to avoid too much under/over exposure on the video, ~ shoot progressive or post process interlaced footage to progressive
For 3d it's looking for the same kind of results through a different workflow, but lighting is still going to be a big one.
For either you can do some post work too, look at some light tweaking of the curves to a more film like "S" shaped response, think about the colour look, and maybe add camera filters in post (grads and diffusion most likely).
In general video mostly looks like bad video because it was shot like bad video. If you spend time setting up the scene and generally following film production values it will look a lot better. Now just do the same with the 3d
Hype's Special trick
import your footage twice. it'll come in as either upper field first or lower field first (under Interpret Footage - Main). Change one of the imported files, so you have one of upper and one of lower. drop them both into a comp, doesn't matter which is on top, but make the top one 50% opacity.
zoom in and look at the difference as you toggle the visibility of the top layer - the difference is undeniable. look at people's hair, look at jaggy edges.
if you have really fast action or fast camera moves, this won't work too well, because it introduces a doubling effect on the motion blur of things moving fast through the frame. but for most general shots, this literally doubles your resolution.
and the same effect CANNOT be achieved by simply removing interlacing. Removing interlacing simply doubles the alternating lines of the video, which is exactly the opposite of what this effect is meant to counteract.
I've used this on everything i've ever shot with my 1ccd camera, and the first time we watched footage on one of those 4 foot wide tv's, all my filmmaker friends were asking me why my footage looked better than their 3ccd "filmlook"ed footage. I didn't tell them. Let them figure it out on their own.
I also always color correct to look more like film, and add 2 layers of grain - one big chunky monochrome-in-multiply-mode layer, and one very fine color grain layer. I vary their opacities.