One thing to keep in mind in Orange County is the temperature variation as you move away from the coast. One rule of thumb that people here like to use is one degree per mile. It's not perfect, but it's a decent start. In the summer, 5 miles inland can be 5 degrees hotter than the coastline; 10 miles 10 degrees hotter, etc.
With that said, Newport Beach (and Costa Mesa) itself is a very nice place to live but very pricey. Nice but more affordable places nearby are Irvine and Huntington Beach / Fountain Valley. Irvine is mostly newer homes. The area is nice with some hills and revoluves around the UCI campus. John Wayne Airport is nearby so make sure you look into jet noise when looking in the Newport/Irvine area.
Huntington Beach is also nice and more affordable than Newport Beach. The homes are either from the 60s or new developments. You'll know by looking at them. Huntington Beach has more of a blue collar/mainstream feel relative to Newport Beach. Many of the people that bought the original homes in Huntington Beach worked for the defense contractors with facilities nearby (hence the cultural difference vs Newport Beach).
South of Newport and about 10 miles inland is Mission Viejo / Aliso Viejo. Those are newer affordable areas that are mainly young families.
Let me know if you need more.