I have just stumbled across this page in the policy section of the ntl Home website. Its really useful and details you of what steps have been taken by ntl to improve the service for those with disabilities. It tells you what will be implemented and what has been implemented and that includes Audio Description that was recently launched on Sky. There is a comparison chart looking at the three versions of the EPG currently introduced. It also seems to hint to a third version of the EPG sometime next year which would include the suggested improvements.
There is a list of those channels with digital or traditional subtitles which I know is a FAQ.
To read this, visit this page:
http://www.home.ntl.com/page/epgaccessibilitystat