It does have an adjustable thermostat. I don't see why couldn't get it down to -4F at max setting as I initially had mine at 3/4 setting and it was down to 5F. I turned it up 5/8 setting to hold it at 12F which is what my chest freezer held temp on upper side. Remember, the bottom shelf is about 5F lower than top shelf.

Should be okay as long as you can leave at least 1ft behind freezer and some space on sides to let air circulate. If you can leave door open under stairs, that would be better.

good question. This is a long answer. If you have short attention span. 600hz or 60Hz or 120hz or 240hz jargan is the refresh rate of the TV.

So TV shows or movies for NTSC format are broadcast at 30 frames/second. This translates to whatever they are filming refreshesat 30 times/second. (I am not going to discuss 24hz or 3:2 to keep simple).
To understand i and p at the end of a TV resolution designation like 1080p or 1080i . You have an image that rasters/refreshes across or down the screen. It is decoded either as Interlaced(odd lines and even lines refresh alternating down TV) or Progressive(entire image odd and even lines refresh at same time). A progressive image will theoretically have better fast motion as the image flicker is reduced but it is also very dependent on the refresh rate on the TV.

So if a TV has a 60Hz refresh, it means the TV refreshes the image 60 times/second or 2x the rate of the broadcast or DVD recording. This is fine for movies or shows that do not have fast motion. If there is fast motion, you will get significant motion blur. Motion blur is the artifact where the image is moving faster than the refresh so the TV cannot keep up with the action.

120Hz (4x speed of film) is better but it is still not fast enough for the fastest of action such as someone throwing a football down field and the camera panning fast.

240hz (8x speed of film) is very good at moderate to fast motion but some brands, it makes everything look artificial. That is why you will see a TV now adays say 120Hz native / 240Hz motion where 240hz kicks in when the TV senses large changes in scenes. Problem here is there can sometimes be delay and this creates other annoying artifacts.

With 600Hz (20x speed of film recorded at 30frames), you don't run into these problems as such because the pixels refresh so fast natively that you don't have this motion blur led and LCD screens have.

It has been a plasma standard and unfortunately like Beta max, the better picture gets replaced by cheaper substandard products.

Since plasma is not produced anymore except for commercial use in limited fashion, get a brand with very good software to control motion and stair stepping(jagged lines you sometimes see when motion across screen) These brands are sony, vizio, or panasonic. Make make sure it has 120Hz native as some will say 120Hz but it is a turbo done with software. bad idea. it is okay if 120hz with 240hz "motion". New 4K models with 240Hz native are a big step up from 1080p units with 240Hz native.

Use wired.