I find the "Accessibility features" to be very annoying. I'm not in the target audience for it, so on my machines, I turn it off.
Few things can frustrate me more than trying to compose an email or a post, contemplating my response, when all of a sudden Windows pops up and asks me if I want to enable sticky keys, just because I've had a finger holding down a shift key for a while.
I was THINKING, @#$%^#$!^%!!! And thanks to Windows, I have to start ALL OVER AGAIN!!!
And to top it off, you can't disable it from the dialog box that pops up! See, the dialog box asks if you want to enable or disable, but only has an Okay or Cancel response. So you can enable it, but when you decide to disable it, you cancel your choice, and you're back to where you started. AAARRRGGGHHHHHHH!!!!
There. I feel better now