jinxed - 6:04 am on May 22, 2012 (gmt 0)
I removed them - status code 'Gone', or added a 301 if the content had decent links.
As others have said, moving the content to a sub domain would no doubt see a short term lift, but in the long term (i.e. When Panda is rerun once or twice) I imagine your Panda quality score would be lowered back again.
I would say find the reason G doesn't like the content and fix it, or remove it from the index. I'm personally not a fan or just 'no-indexing' a chunk of content as that still doesn't get to the root of why this content isn't deemed good enough.
Just my opinion though.