Perhaps option 1 will be more resilient.

It could be complemented by a "Create" page for starting a new article, filtering bad titles and using a captcha to limit the vandals.

And another captcha for comment posting, which is already spammed, unfortunately.

I think a flagging mechanism will not be able to keep up with mass defacement.

Another suggestion: a daily dump of article titles, their connectivity and creation dates. I would love to visualize the underlying graph and its growth.

Thank you for such nice site!