Cafe' Du Monde and Muffaletta.. hehe.. Just a little correction there.
You can try James' suggestion for the Muffaletta or go to Cafe Maspearo's for one. It is located right near Jax Brewery which has plenty of nice shops, stores, etc.
The Riverwalk is nice also. If you do venture toward Bourboun and are looking for the bar scene, you have Pat O's of course as well as other favorites like the Cat's Meow.
Say hello to the one eyed guitar player for me.
Oh yeah, St. Louis Cathedral (Jackson Square) if beautiful. Jackson Square usually has plenty of street performers, artists, etc. to entertain you.
If anyone bets you a dollar that they can tell you where you got your shoes or that they know how many kids you're dad had, don't bite.
Beware of street hustlers and pickpockets in the "quarter"..
1ARUNEM <-- grew up in New Orleans..
P.S. don't forget the drive thru Daquiri shops..