I haven't bought a DVD in a while thanks to Netflix, but the re-release of the Terminator 2, got me curious, here's the latest state of the art in DVDs:
* Superbit Deluxe DVD series from Columbia TriStar. Superbit releases from Columbia TriStar have a higher video rate of 6-7Mbps and have higher data rate DTS and a 448 Kbps Dolby Digital Soundtrack. They have a second DVD with all the extras. The original Superbit DVDs were only a single disk and didn't have any extras, but at least they looked marvellous.
* "DVD Scan":http://dvdscan.com/. My favorite review site. I know the movies I like, this one measures the actual quality of the DVD technically, so you know that the transfer is good.
* "DVD Review":http://www.dvdreview.com/I used to read "Widescreen Review":http://widescreenreview.com, but this site went all pay. DVD Review is the top ranked by google site for DVD reviews, but most of the reviews are pretty old and subjective.
* "Upcoming Discs":http://upcomingdiscs.com. At least has scores for the various criteria. As an example, "Terminator 2: Ultimate Edition":http://dvdscan.com/t2.gif is the latest release and it scores an amazing 9.96 while they love "Total Recall: Special Edition":http://dvdscan.com/totalrec.htm