Best neighborhoods for 30 something single professionals to live in if working in Rosemont?

It sorta depends on what you're like. If you like it quiet and safe, Forest Glen is a great option. If you prefer a more happening area, you might want to venture further into the city to Wicker Park. It's really more about how you feel about traffic and what your issues with nightlife are. Rogers Park and Uptown can also be great choices, but you'll have a bit of a drive every day.