Greetings:
in a nutshell, there is no "best" health insurance; rather, it's whatever works best for you. Hmos are great for growing families, but you cannot go outside of your network (unless it's for a medically necessary emergency visit, where medically necessary is determined by the hmo, not you).
Ppos offer more flexibility in that you can go outside of a network, albeit the insurance will cover less. You should, however,
read the fine print, as some ppos won't cover out of network.
There are also other insurance companies that don't have networks: you can go to any doctor, any hospital.
It all depends on what's important to you.