I strongly encourage players to choose to play human PCs in this campaign. This is primarily for story reasons as much of the campaign does takes place in Ravenloft, where they may burn people that look different than them.
You may however play any other race from the Player's Handbook, except for elves and half-orcs. There is open bigotry towards elves in Hurva. You will not find any elves (aka faeries) within any human settlements. Orcs and all of their kin are not considered redeemable creatures in this campaign and human-orcish hybrids are genetically impossible.
Half-elves will have some severe social problems due to their heritage. Examples of these include, not being served food, charged 2-10 times as much for supplies and not being allowed in certain towns or establishments.
Also note that I am most likely going to be rewriting the racial traits for all of the demi-human races. Since there are no demi-human PCs at the moment, it will most likely be one of the last pieces of this project.
Human Racial Traits As per page 13 of the 3ePH with the following changes:
No bonus languages. (see Chapter 4, Skills)
Literacy: No character can not read & write any language unless they specifically take that skill. In general, most of the population is illiterate. Exceptions tend to be the populations of the major cities which have a higher percentage of literate individuals.