IMC, the main player character races -- human, elf, half-elf, dwarf, gnome, and halfling -- are generally treated as equals. A dwarf may get along better with a dwarf, and there are isolationist elves, but in the main "civilized" areas, race of that sort doesn't matter.
Half-orcs are a different matter -- there is a degree of racism against them. Some are treated as "regular people", but most have at least a little suspicion of them, and they are indeed a lot more likely to be poor or criminals in my campaigns.
Monster races -- actual orcs, kobolds, goblins, giants, etc. -- aren't so much subject to racism as they are just viewed as an outright threat. The PC's allied with Meepo and snuck him back into Oakhurst, and nearly got in a barfight with a hotheaded local when he found what they had in the barn out back of the inn!
Lizard men are a special case among the monsters -- they are feared much more than half-orcs, but not necessarily seen as nothing but a threat. Sometimes they get along with humans and be somewhat accepted, but always as an exotic alien presence.
Finally, I also have races among my humans, as I'm running my version of Greyhawk. Since my campaign is set in Bissel during a war with Ket, there's often some suspicion of the Baklunish. Suel v. Oeridian v. Flannae is sometimes noticed, but there's rarely racism between them.
I also have Cauldron in my setting, and my Cauldron is a colonial slave society. Here's my write-up on the races and slavery in Cauldron, for my version of it:
The founders of Cauldron and the majority of its population came from the north, across Jeklea Bay, from the noble Kingdom of Keoland or the Hold of Sea Princes, a nation of pirates who broke off from Keoland ~CY 450.
The largest race in Cauldron are Suel (think: Northern European), who originally were refugees from the ancient (1000 years ago) magical Twin Cataclysms that ended a great war, and who form the bulk of the population in both Keoland and the Hold. Many other Cauldron folk came from the eastern reaches of the Azure Sea -- mostly Oeridians (think: Southern Europeans) from the city-states of the Wild Coast (including the City of Greyhawk) or the now collapsed Great Kingdom and its successor states. A few Touv traders (think: Africans) from the tropical island continent of Hepmonaland also settled in Cauldron long ago.
When profitable diamond, obsidian, and iron ore mines were developed in the region, gnomes and dwarves from the Sheldomar Valley (Keoland and environs) flocked to Cauldron, and halflings came with them. The city has about 7500 adults, making a medium-sized city by medieval standards.
The slaves who work the plantations that provide "The Shackled City's" wealth were captured generations ago in the Amedio Jungle -- they are Amedi (Suel tribesmen who degenerated to a Stone Age culture after fleeing the fall of the Suel Imperium) and Olman (think: Aztec) tribesmen, whose jungle city-states mostly crumbled long ago. The lowland plantations around Sasserine in the river valley in between grow sugarcane (which is processed into rum), bananas, and rice (for local consumption). The highland plantations around Cauldron grow coffee, cacao (for chocolate), and durian fruit.
The climate around Cauldron is humid and tropical. The jungles and lowlands are plagued by malaria, dysentery, and wild animals including great cats and even dinosaurs.
The city-dwellers, on their mountain top, escape the oppressive heat of the jungles, and their water, from the caldera's lake, is magically kept free of disease. Slaves are not allowed in the city proper.
The major religions in Cauldron are Kord (Suloise god of strength), St. Cuthbert (Oeridian god of common sense and righteousness), Wee Jas (Suloise goddess of magic and death, former patroness of the Suel Imperium), and Pelor (Oeridian god of the sun and healing). Worshippers of Fharlanghn (Oeridian god of travel and open road) are common among the small elvish population, but have been denied permission to build a temple, due to their strident opposition to slavery, which the churches of St. Cuthbert and Pelor also sometimes quietly oppose.