If you know about the Criterion Collection already, you don't need any convincing to check it out. Every person who comes across it will become a Criterion junkie.
For those who are not familiar with the Criterion Collection, it is probably the greatest company in the world, no exaggeration. It is the best collection of movies on DVD, hands down, with tons of great special features for every movie. They release every possible type of movie, from classic American movies to European masterpieces to rarely-seen cult sci-fi flicks to the weirdest experimental movies to brand new art-house movies to everything in between. If it's a great movie, Criterion gets its hands on it. To receive the 'Criterion treatment' is the best thing that can happen to a movie.
Each DVD gets its own spine number based on the DVD release date. If you want to get into cinema, you could just start with Criterion spine #1, Renoir's The Grand Illusion, and watch them straight through to Chaplin's The Great Dictator, and end up something of an expert. This would be especially true if you checked out some of the awesome special features. DVD special features are usually pretty half-assed and wastes of time, but this is rarely true for Criterion. Vintage and new interviews and commentaries by filmmakers, critics, and scholars are put alongside short films, behind the scenes footage, trailers, alternate scores, anything they can come up with.
Criterion also has the Eclipse series, which is usually collections of very rarely seen movies, like the documentaries of Louis Malle, or the early silent films of Ozu.
The DVDs themselves can get a bit pricey, but there is no need to actually collect the Collection. I personally own only two Criterions. You can rent almost all of them on Netflix, and most excitingly....
http://www.hulu.com/criterion
on hulu plus, for 8 bucks a month, you can stream Criterion titles. 150 of their movies are up there now, but they'll soon be including about 700 more movies, every movie that Criterion owns the streaming rights for, which includes a lot of titles that are not even out on DVD, some stuff the public hasn't seen or remembered in decades.
It's an exciting time to be a Criterion junkie.

The only bad thing about all those Criterions going up on hulu plus is that Criterion is going to stop putting their titles up for Instant Watch on Netflix. They say all their Netflix Instant titles will be off Netflix by the end of the year. I think it's going to take a little bit longer than that, since some titles are already contracted to be on Netflix into 2012. Regardless, Criterion on Netflix Instant is fast going away. The DVD's will of course still be available.
The Criterion website is also pretty great. http://www.criterion.com You can browse the collection by title, year, director, country, or genre. They have a bunch of themes and people and 'celebrity' Top Tens on the site as well. And they have tons of essays either linked or uploaded onto their own site.

Personally, I am right now two thirds of the way through this 'Three Films by Hiroshi Teshigahara" box set: http://www.criterion.com/boxsets/458-three-films-by-hiroshi-teshigahara?q=autocomplete. The first two have been really great, and, as per usual, the special feature, in this instance a video essay by critic James Quandt, have been fascinating.

you spam-cunt-bot cocksucking piece of blood-stained-shit fucking cockroach you goddamn it

Criterion is also well known for its beautiful and creative cover art. a la







<--anyone recognize this one?

For a small fee, I may be able to finagle an introduction between you and loathedvermin72

I actually know of another message board where he posts.

The Adventures of Antoine Doinel box set is the gem in my DVD collection.

You're killing me the argonaut.

The Killer is the pride & joy of my DVD collection.

easily the greatest film (and criterion) until The Tree of Life comes out

Does this have anything to do with the Criterion Brothers in Funny Farm?

I can't remember which movie it's on, either Army of Shadows or Le Deuxieme Souffle, but it has what is probably my favorite Criterion special feature. I think it's the latter movie, and it's a bunch of interviews with director Jean-Pierre Melville and actor Lino Ventura. Ventura is very intelligent about acting and what it entails. I sometimes think of screen acting, and filmmaking in general too, as almost undignified, wasteful, and self-indulgent. (Les Blank's documentary, Burden of Dreams, which is about Herzog making Fitzcarraldo, illustrates this point perfectly, and hey it's also a Criterion release.) Ventura and Melville restored my faith. Definitely check out that special feature if you rent the movie.

Are they ever going to release Stalker on blu-ray?

I always forget about Blu-ray. I've never watched a Blue-ray, I don't think I've ever even seen an actual Blu-ray (disc?) outside of its box. I guess I just don't run in circles with people who have enough money to do things with Blu-rays.
But yeah, Criterion is slowly but surely putting their back catalog out on Blu-ray, too.
However, the only Tarkovsky movies now out on Criterion are Andrei Rublev and Ivan's Childhood.

I had no idea that backspacer was a criterion edition.

I only started watching blu rays a few months ago and it's so much better, Stalker would look stunning in HD.
I would pay a lot of money for a complete Tarkosvky blu ray box set from Criterion

this one is much better

Solaris is also out on Criterion, with a blu-ray release scheduled for May 24.