For testing, your best bet is
$1. It's up to date, follows all the standards correctly, and is free. It's been my main screen-reader for 10 years, and I would never go back to the expensive commercial alternatives.
As for web accessibility, Drupal is doing absolutely incredible things there. Not only does the Drupal CMS create accessible content by default, but they've made the administration and content creation portions of the system completely accessible, as well. It happens far too often that developers make the public content accessible, but apparently assume that no blind person will ever work at that company, or no blind people ever want to generate there own content. Wordpress used to suffer from this problem: it could make accessible blogs, but the administration and posting sections used to have huge access issues. Over the last year or so, though, they've made huge strides in fixing them. However, I still find it far easier to picture a Drupal theme in my head, and it seems to be better at not making ugly websites when the person responsible for choosing themes and layout is totally blind. But that could just be because I've had more experience with it.