Texas is full of Mexicans and many other Latinos of various countries. As well as Asians - Chinese and Vietnamese and Koreans. Africans. Muslims. Etc.
There is a portion of Texas along the east and northeast (well north of Houston) that has been known in the past (like, 60's, 70's and maybe early 80's) for some idiotic racism, due to some hick sheriffs who did some stupid and violent things. We cleaned that crap up.
Texas may have a stereotype about racism, but certainly the large cities are fairly well integrated and we don't have any more of a racial problem than any other state (or country, for that matter). I've never known people in West Texas to be racist either, but I spent most of my time in Houston, Austin, Dallas/Ft Worth and San Antonio, so who knows. But I doubt it - no more than anywhere else.
Southwest and West Texas is largely, if not mostly, Latino.
We won our independence from Mexico, and when we did, there were plenty of Mexicans that helped form the Republic of Texas and later join with the US. Texas is proud of its Latino heritage.
The biggest racial problems I know of that exist are organizations that promote illegal immigrant rights. Even Latinos who came to Texas legally (whether their families were part of the creation of Texas, or they came later) resent the illegal immigrants, for most part. Illegal immigrants don't integrate with the society, like the rest of us do quite well.
To say that Austin, in particular, would be a bad place for any Latino - well, I don't think you've been to Austin, or perhaps visited and were wearing preconceived-notion blinders.
I believe Argentinos would feel right at home in Texas.