My favorites:

1. The Criterion Collection - This one is the obvious choice. Fascinating semi-obscure films with the best possible transfers, loads of features, and the best packaging out there. I once heard someone describes them as "The Porsche of DVDs"...so true.

2. Anchor Bay - Easily my favorite horror DVD company. They may not always release the best possible editions, but other than Criterion, they put out the most titles I'm interested in. And wowee is the Dawn of the Dead Ultimate Edition breathtaking.

3. Warner Bros. - They used to be really, really bad with all that bare-bones snapper case crap, but they've really cleaned up their act in recent years. Some of the best Special Editions out there with some of the best packaging this side of Criterion. The Gone With The Wind Collector's Edition is just awesome.

4. 20th Century Fox - They've done some really great work and have had consistently excellent transfers. The Alien Quadrilogy was simply spectacular - two versions of each film, a special feature disc for each film, and an extra feature disc...they really gave these films the royal treatment. The Star Wars Trilogy and Fight Club Special Edition are damn good as well and both feature exceedingly good transfers, especially the Trilogy - Episode V looks fucking stellar.

And Blue Underground, Lion's Gate (The OUTSTANDING transfer they gave High Tension and the pretty much perfect The Devil's Rejects DVD), and Elite Entertainment (Re-Animator and Night of the Living Dead Millennium Editions) have been doing some good work as well.

The worst (other than cheapie releasing companies, that is):
1. Paramount - Truly, a company that fails to understand the potential of the DVD format. The majority of their stuff has just been pathetic. The awful transfers they gave The Godfather films, the cut and rated Friday The 13th boxset...just embarassing. At least they did a pretty good job with Indiana Jones set.

Definitely Criterion and Anchor Bay.

You know an awful lot about DVDs.

Madman
Dendy

my favorites:

20th Century Fox
New Line Home Entertainment
Super Bit
Sony Pictures


Warner Bros? well they got a great couple of released quality dvd transfers but ... have you seen all those Harry Potter & Batman movie releases? dear god man, all of those video transfers suck so much ass.

Fox

Super Bit's not really a DVD releasing company. They're more of a mastering system, like THX.

And personally, I don't give a fuck about Harry Potter or Batman. I'm referring more to their SEs and restorations. Gone With The Wind, the original King Kong, Citizen Kane, Doctor Zhivago, The Mission, The Adventures of Robin Hood...those DVDs are just awesome, man.

d'oh! forgot about the super bit thing.
if you check out just for a few seconds the opening scene from hp 4, black screens are the death of Warner transfers, which is funny that they are all dual-layer dvds. if it was single layer, i would understand.

of course when it comes down to their box set versions, they gotta lay the transfers to the max. but their single released 1 or 2 disc (special feature) dvd sets, they won't care.

but i must say, warner did a fantastic job on Matrix, the first movie. when they released the 10 disc box set, i was blown away with the version. what do you expect when the first release the movie on dvd back in '99 included hours of bonus footage on 1 disc along with the movie.

another company i have to say is also doing a find job is RHINO. bringing back many of the old cartoon shows to life, and transfering the old tapes to dvd. got the complete transformers collection and i must say they did a great job on them.

Vivid

i like focus films because they seem to have a lot of great movies that i otherwise would never hear about. they don't always have all the flashy packaging and extras but they do put out some fine indy and foreign films.