Can someone who has the DVD check it for me? (Really poor PQ)

I hadn't enjoyed the film in a while, so I decided to toss in my disc the other day and give a watch. Apparently I didn't notice it when I first bought the disc a few years back (I may have been watching on a smaller display), but this time around I was keenly aware of persistent macro-blocking and other artifacts in the video, particularly during fast-moving or dark scenes (which as you know, there are a lot of!). I found it very distracting. Out of curiosity I popped the disc in my computer drive and discovered that the entire movie takes up a mere 3.77GB, and that's with two AC3 soundtracks! Checking the film's bit rate, I found that it averages around a (miserable) 4,100 Kbps.

I find it hard to believe they recorded the masters at this bit rate, so they evidently compressed the sh!t out this. Why?!? I mean for God's sake, the video doesn't even come close to filling a single-layer disc, and I've seen home movies with better encodes than this.

Anyway... I know that there are a few different DVD versions floating around, and I would appreciate if any of the DVD owners could take a look at their own disc and determine the total amount of space being taken up by the video files. And if you know how to check it, reporting the overall bit-rate would be illuminating as well.
I'm wondering if all the DVD editions/presses were like this? And I'd really love to know what they did with the Blu-ray. For the record, my own DVD version is "The Raid - Redemption", Unrated, and produced in 2012.

Thanks in advance to anyone who can post the info here.