Some sample adult model release forms via Google:
http://www.google.com.au/search?num=...G=Search&meta=
2257 form:
http://www.freespeechcoalition.com/w...ectionForm.pdf
Take a photo of your models holding up their license next to their face.
Also, have a long and serious talk to everybody that is thinking about appearing in your videos. They need to realise that once it's out there, there's no getting it back. Will they be happy if their family finds out? Are they willing to have this in their background? Will it jeopardise their employment?
Making a DVD is a difficult option because you have to consider the problems of meatworld distribution. Then again, doing websites is not as easy as it used to be.
And yeah, get a lawyer, join the Free Speech Coalition.