Robert,
For a live DVD, you've got to go to at least 2 audience mics. Go 4 if you can and want to go surround. Give them stereo crowd at least. This is not so much for during the songs, but between them...the screaming/fainting/hysteria...or not. The better your positioning, the more you can use these mics during the songs as the crowd clap/sing along.
I've had good results from using tight mics (Senn 416's) slung from the front truss...inside (width-wise) the PA, and slightly behind, pointing about 1/3 of the way into the audience, and towards the centre. Hard pan them in the mix.
For the second pair, try them at the FOH mix position - assuming it's centrally located, and not against the wall - aimed towards the back of the room. These can be the surrounds.
Good luck.
Cheers,
Tim