My english is better than that of conservative Americans

[Rev. Rye]

Do you think it is foolish to suggest that only the combination of a penis and a vagina can produce a baby?

Maybe about 100 years ago, you would have been right. As whateverist noted, artificial reproduction is an effective means of producing a baby and has been used effectively with humans for decades. In fact, there have been experiments to create babies by inserting donor DNA into an empty ovum and inserting that into someone else's uterus, which, potentially, would not even involve the penis and the vagina. Granted, it's never been done on humans and even in the animals, they still haven't worked the bugs out.
In short, regardless of the ethics of the procedure, it works.

Do you think it is racist, or something like that, to suggest that heterosexual sex is more biologically correct because it can produce a child?

First of all, define "biologically correct" and what the fuck relation it has with ethics.
And your query opens up another one: What is the moral difference between a man who is in a relationship with a woman who is unable to bear children (or vice versa), and two men or two women in a relationship. I ask this because, if your basis for homosexuality being wrong is that gay sex cannot bear children, that would mean heterosexual sex where one partner is infertile is equally wrong.
Finally, the term would not be racist, but "heterosexist."
Also, given that, whether or not you choose to acknowledge it, homosexuality has been repeatedly shown to have at least a partially (if not totally) biological basis, and you can check out some of the studies that demonstrate this here; wouldn't that make it, to a degree, "Biologically correct"?