Please answer without spoilers! I want to play a race that's hated most across Skyrim. I know bethesda game don't really differ in race choice unlike bioware games, but still I want to know if there are even minor difference regarding NPC's attitudes towards PC.

I'm guessing it would be either argonians or dark elves, right?

Khajiit. The Dunmer and Argonian problems really only happen in Windhelm, but Khajiiti caravans are barred from entering any city.

Altmer.

Edit: Something tells me that this thread will derail into a grey quarter argument thing.

Those damn cats.

... then the lizards.

Khajiti easily. They're the only ones actively banned from Skyrim's cities. Argonians and Dunmer have their problems in their own areas but it doesn't compare.

Probably the second most universally discriminated race is the Altmer, less so in the Imperial west of Skyrim, but there's still many Imperial-Nords who have a certain level of disdain to the Altmer because of the Great War.

I should probably point out that this matters little for the player character though, race is an aesthetic choice and only a few bits of dialog will ever make it feel like you're not just playing a Nord anyway.

Altmer: Englishman in New York

Khajiit: cat in the larder

It's orcs. They have ugly teeth.

And they're pretty dumb and homeless!