I hate best country questions, because without what your criteria are it's impossible to give an answer. Best public transport? Best protection for disabiled people in the job market? Most things in braille? Best disability benefits system? Without knowing what's the most important thing to you I can't really hope to give an answer aside from that northern europe is generally better than southern or eastern.

I'm not completely blind, and have traveled all over the EU. For the most part all the country's are pretty good,so a little better than others but I have found the the common person is always pretty helpful as long as you don't mind the 20 questions game.