OK, here we go. I'm the resident PF guru around here so I should be able to help you out.
In the way of DVD's there's unfortunately not a whole lot of stuff out there yet. Mainly what's out there (at least in terms of strictly Floyd) is Live at Pompeii, The Wall (the movie, not a concert), and Classic Albums: The Dark Side of the Moon.
I wouldn't recommend getting Live at Pompeii if your husband doesn't like pre-Dark Side stuff. It's pretty trippy stuff, long psychedelic compositions with little singing and a lot of noise. Also, a dog howling the blues for 3 minutes. Unless your husband is a hardcore Floydian, I wouldn't recommend it, at least not yet.
Now, as for The Wall, it's a movie, not a concert. It's the film that basically shows the story of what the album The Wall is all about; a rock star named Pink slowly going nuts. Bob Geldof plays Pink, and it's not a bad movie at all (if a bit freakish sometimes). Not a bad choice, but like I said, it shows no concert footage, and Pink Floyd isn't actually in the movie, just the music from The Wall in behind.
Classic Albums: The Dark Side of the Moon is a good choice if your husband is a fan of that album, but there's no live footage at all, it's basically the band being interviewed about how it was made. It's old interviews and a bit of old footage edited together. Not worth the price unless you can find it under about 15 bucks.
Now there's some Roger Waters DVD's out there that are good too.
There's the Wall Live in Berlin, which you've already said he has. But th best of the pack (at least until PULSE is released on DVD), is Roger Waters: In the Flesh.
It's Rog doing about 2 hours of Floyd songs with an excellent backing band on his most recent 2001 tour. He also throws in some very good solo songs too.
I would recommend getting Roger Waters: In the Flesh. I guarantee your husband will love it.