Bjork's other stuff is great too.
I'm not too keen on the Vespertine stuff since my heart is with Homogenic. So I would recommend the Live at Shephard's Bush thing but be warned of the accordian appearances. I find it ruins the songs.
But there are some fabulous remixes on that. With an awesome girl Dj. Forgot her name.
But the best one for me is still the the one with the string section, Live in Cambridge.
For some reason, they put it in the Vespertine section at Bjork.com when there are no songs from that album on that dvd. *shrug*
Is this the one you're talking about?