"Wedding Crashers" starts out so well that you think it can't possibly keep up the pace. And then, dammit, it doesn't.

Scripters Steve Faber and Bob Fisher lay out their premise with economy and style: Vince Vaughn and Owen Wilson are best buds who wander uninvited into weddings to score free food, drink and women, but run into trouble when Wilson really falls for a bridesmaid and drags Vaughn along to a nightmarish weekend with her family.

The first hour, is constantly, consistently great, with Vaughn and Wilson at their off-kilter best; Vaughn's motormouthed performance might be his best since "Made," and Wilson's ability to undercut sleepy-eyed innocence with mischievous, dirty glee makes him a great choice for the role of a player sideswiped by puppy love.

Oh, and Rachel McAdams is an ideal choice for Wilson's slightly cynical love interest, the middle daughter of a political heavyweight played Christopher Walken, who can say "Wanna play some touch football?" and turn it into a bebop symphony.

Isla Fisher, as the unbalanced younger sister who makes Vaughn her personal sex poodle, is very funny. And Keir O'Donnell, as Walken's black-sheep son, gets laughs just by showing up and sneering.

But "Wedding Crashers" is two hours long, and it doesn't need to be - director David Dobkin gets greedy, and lets the plot's last 15 minutes stretch out for 45, smothering the comic momentum with one unnecessary scene after another. (The director's cut adds another nine minutes, for a grand total of 128 - and yeah, the expanded cut of "The 40 Year Old Virgin" ran even longer, but that film made its breadth feel like an asset.)

This isn't to say "Wedding Crashers" doesn't have some good moments; just that there aren't nearly enough. By the time Will Ferrell shows up for the obligatory frat-pack cameo, the movie's gone from being the most entertaining guest at the party to the guy who can't understand why everyone else just wants to go home.

New Line is applying the same split-release strategy to "Wedding Crashers" that almost every R-rated picture warrants these days - the theatrical release gets its own enhanced-widescreen edition, in order to give Blockbuster and Wal-Mart something to sell, while the director's cut is released - in separate full-frame and enhanced-widescreen discs - as an unrated, "Uncorked" edition.

The supplements start with two audio commentaries: There's the usual "everyone was great" prattle from director Dobkin, and a second from Wilson and Vaughn that's rather charming in its honesty - they get bored, they take breaks, they bring food into the recording booth, and so forth. It's the same easy chemistry that drives the movie's first hour ... and, oddly enough, it runs out of steam well before the final credits.

The rest of the package includes four deleted scenes (including a priceless karaoke performance of "99 Red Balloons"), two production featurettes, a list of wedding-crasher rules ("Your favorite movie is The English Patient") and a collection of trailers.

The extras are essentially the same on all the discs - well, the commentaries on the R-rated disc have been truncated to fit the shorter cut of the film - and the "Uncorked" release also includes the theatrical cut, so there's really no reason to buy the R-rated release unless you're worried about offending someone else in your house. Of course, there's offense aplenty to be found in the the R-rated version, so it's kind of a no-win situation.