What happens when an albino person and a really dark person have a child together?

Most likely normal. The albino has two recessive albino genes and will give one to each of his/her children. The other parent probably has two normal genes so all the offspring will look normal but all will carry one albino gene. In the extraordinarily unlikely event that the partner carries one albino gene of the correct type, then 1/2 of the children will have albinism and 1/2 will be carriers. Rare!