I would let her initiate any physical contact like a hug.
As others have said, get out of your car and ring the doorbell, then open the passenger door for her. These aren't strict rules, it would just be a general courtesy thing. It's best to pay attention to what she responds to, whether she prefers you open doors for her or not, etc. Ultimately this is about what works for her (and for you), and less about doing everything "right" (there is no universally right way to approach this).
Opening the door from the inside could feel like you aren't excited to see her, or can't be bothered to get out of your car to greet her. Letting her open it while you sit in the driver's seat similarly feels "chilly" like you're disinterested.