I did not know about the open source definition. Is that just a guide line or does it carry some weight?

It carries the weight of the names of the people who support it. Take a look at who is involved in it. Ian Murdock, founder of Debian, is a co-founder for the OSI.

Also, is it discrimination if I give users a choice? You can use my software whoever you are, you just have to disagree with racism.

Rephrasing it doesn't change anything.