Good Neighborhood to Stay in While in Paris and a Bunch of Restaurants Too!

A friend of mine is heading to Paris for the first time.  And I have another American friend who has been living in Paris for the past few years with his wife and kids...

So the questions were:  

1) What neighborhoods in Paris would you recommend trying to stay in (our plan is to rent an Airbnb)?
2) Are there any must-try restaurants you would recommend? We’re both pretty active so are open to seeing the city on foot, and in terms of food we love everything from nice and fancy to casual and tasty.

And my friend Michael answers:

1)  Stay in the 6th, by Jardin du Luxenbourg. Magnifique.
2)  Restos...hmmm

• Monsieur Bleu, ask for outside. No brainer.  It's our go-to!
• Frenchie get reservation now (or Frenchie Wine Bar if you cant get rezy at main. Same alley. It's no reservation. Get there early and wait a bit.
• Spring
• 404... Great Moroccan
• Hotel du Nord (supper club I love)
• Hopefully the outdoors is set up.  Places on The Seine will be set up. Wine at "Flow" is special
• L'Avenue is always good

So there you have it!  Bon Appetit while in Paris!