Katawa Shoujo's premise doesn't sound promising. A dating sim where you choose between several disabled girls could very easily turn out as an objectification of disability and girls, with a freakshow tone to it. But surprisingly, it's not like that at all.
Firstly, each of the girls has a unique personality, with many having traits that are completely unrelated to their disabilities. The blind girl Lilly, for example, is a very cultured half-foreign girl; and the armless girl Rin is an artist with a very unusual perspective on things. While many characters have angst, all of those characters have reasons other than disability to angst (Hanako, who has a bad facial burn, lost her father in the fire that burned her). The protagonist also has a disability as well, a heart problem which almost killed him and resulted in him being sent to the special school where the story takes place. This heart problem can actively impact your character during the storyline, especially if you end up with Emi, the legless track star.
And secondly, the approach to dating these girls is a very healthy one. As a visual novel, it has a structure similar to Choose-your-own-adventure books, so a few choices in the beginning determine which character you'll end up with - if you get a good ending (you can also get bad endings, one example being falling off a roof and dying). Then, you proceed to befriend the girl you chose, get to know her well, and only then does the relationship become a sexual one. It's usually the girl who initiates this shift, incidentally.
There is some explicit content, which you can choose to turn off if you wish. My brother has played it both ways. But the explicit content in Katawa Shoujo is far better than any porn you can find, because it's depicted in the context of a caring, healthy romantic relationship. You know the girl well and care about her deeply long before the sexually explicit interaction with them. They also provide a model for how to handle the sexual aspect of the relationship as well. With one girl, the second time you have sex with her, the two of you decide to try something unusual, which it turns out the girl really doesn't enjoy. She honestly communicates this to you and you both make the decision never to engage in that particular sexual practice again. (Also, every instance of sex in Katawa Shoujo includes condoms.)
My brother is a heterosexual teenager. Someday, he will be sorting out these questions for real, when he gets over his shyness enough to start a relationship with a girl. And if he follows the model of Katawa Shoujo, I think he'll make a great boyfriend for whichever girl is lucky enough to have him. And if he ever gets involved with a disabled girl, Katawa Shoujo will have shown him that there's a lot more to that girl than her disability, and that having a disability need not be a barrier to having a relationship.