I think that’s the right term, but I’m not sure. On every DVD I’ve ever seen, there are “markings” like the one in the following picture, which I’ve highlighted with a white square. There was a bit of downgrading in turning it into an image file, too, but most of it is in the original picture.
What is it and is there a way to get rid of it? It’s kind of obnoxious and distracting to me.
It’s called “The Abyss”
Kidding, kidding, I even sort of liked that movie
I’m not exactly sure what it is that I’m meant to be seeing in the linked image, but if you’re asking about blocky artefacts and pixellation on DVDs in general, it’s because of the compression scheme used to fit the video stream into the space available.
DVD video is encoded using MPEG2 compression - a good overview of how this works can be found on the Wikipedia page for MPEG 2.
There may be a number of reasons why artefacts appear, but they all more or less boil down into two groups:
-the image or footage being too complex, or too fast-moving to be adequately encoded at the selected bit rate
-problems reading the data from the disc in the player, perhaps caused by dirt, scratches, flaws in the media, or occasionally because the player cannot adequately process a stream encoded/compressed at a very high bitrate.
I also can’t see what the problem is in the white box (except that it’s a very dark image). But as Mangetout says, it’s likely to be compression artefacts and if it is then there’s likely nothing you can do about it – if the data has been lost to fit the video on the disc then it’s gone for good.
That’s the problem with digital image formats - the quality absolutely sucks compared to a good analogue signal. British digital TV is especially appalling: a lot of the channels look as though they have been compressed using a sledgehammer.
But it’s more diffricult to get a good analogue signal. Digital signals remain at their original quality until there is enough noise in the communications channel to make distinguishing bits difficult. If you are watching a badly-compressed digital signal, that is a choice of the signal-provider, not an inherent limitation of the technique.
In other words, blame management. 
I appreciate that, but when you’re in an area that has excellent analogue TV reception, it’s frustrating to know that in a few years you’ll have to put up with cruddy digital picture quality thanks to too many channels being shoehorned into too small a frequency range. (Caused, of course, by the government selling off as much space as possible.)