No stones here, Ironwoman .
I feel very much the same as you, especially having watched a friend carry a child with no higher brain, just a bubble sac, until the 7.5 month. They were 100% sure of the diagnosis. She knew the child was incapable of quality or length of life at 16 weeks, yet continued carrying the baby because abortion wasn't an option. It was a horrible situation.
Prior to seeing this, I believed that no one had the right to abort, ever. Part of that, I'm sure, was my JW upbringing, but part was because I had no actual experience with anyone who had good reason to terminate. I think this situation made even more impact on me because I saw how much more torturous it was for her NOT to abort.
As far as disabilities of a more "normal" kind, I've seen a lot of joyful, productive disabled children and adult. One of my first real jobs as a young adult was as a teacher's helper in the "special needs" preschool system for Yamhill County Educational Services. It was hard, but rewarding. And I realize that many of those children might have been aborted if it had been 15-20 years later when genetic screening is almost routine.
From another perspective on disabilities... are we simply talking about disabilities that can be seen by the impartial observer? ie: physical deformity, impaired gait, speech, developmental disabilities? I think that there are plenty of disabilities that are not labelled as such because they don't really have an outward display. For instance, as long as I can remember I've suffered from severe migraine. Sometimes I'll go weeks without one, but sometimes it will be 3-4 days of a week, for weeks at a stretch with a migraine. Is this a disability? I'm suffering... does that mean my quality of life is poor enough to have never lived it? I don't think so.
In my personal opinion, situations such as Fe203 describes, and my friend went through, fall into another category entirely. I'm glad your mother didn't abort you, Randy, but the issue is certainly not as clear as delineating "disabled/non-disabled." There are absolutely degrees of magnitude difference between the child with mild Down's Syndrome, and the child with no rectum, an incomplete bowel, no functioning kidney and a partial brain.
Medical science has made great strides in birth viability. I am thrilled that the child with a hole in his heart, but no other issues, can now have a (relatively) simple, though risky procedure to close the hole. With surgery, the child lives a normal life, without, it dies. It's fairly black and white in that instance. I do have strong issue though, with putting a child with no chance of quality of life through endless surgeries, treatments and therapies--only to result in a child that can live without life support, but cannot truly "live." I've seen it, it makes me very sad. Is this an ethical use of medical ability? Perhaps this is a case for termination, or at the very least letting nature take its course.