If you're thinking about the physical meaning of a "ghetto" as a densely populated, impoverished, and often segregated neighborhood:
* Affluent neighborhood
* Upscale community
* Suburb (depending on the specific suburb)
* Exclusive enclave
* Luxury housing
If you're thinking about the social meaning of "ghetto" as a marginalized or disadvantaged group:
* Privileged
* Empowered
* Mainstream
* Integrated
* Inclusive
If you're thinking about the cultural meaning of "ghetto" as a place of creativity and resistance:
* Uptown (in the sense of a culturally vibrant and influential area)
* Mainstream (in the sense of a dominant culture)
* Establishment (in the sense of a powerful and influential group)
It's important to remember that the word "ghetto" can be used in a derogatory way, so be mindful of the context and your audience when choosing an antonym.