They make a mean steak in New Orleans. Also, cajun catfish. And of course the crawfish. The only thing I miss about the Deep South is the cajun catfish.
The center of attraction in New Orleans is Bourbon Street in the evenings. During the day, you can take a dinner tour on a paddle wheel boat down the Mississippi river and back, and visit some antebellum plantations. You can buy the tickets for the boats at the end of Canal Street at the riverfront near the mall.
If you are going to party in New Orleans at night, the hot spots are the Cat's Meow and Pat O'Brien's pub.
I prefer Pat O'Briens. The Cat's Meow is for 20-somethings who can't handle their liquor.
And since you are from Ireland...Pat O'Briens.
Stick to the tourist ends of Bourbon Street and Canal Street.
Do not venture off the beaten path. New Orleans is a very dangerous place. If you travel down Bourbon Street, with Canal Street at your back, and you eventually come to a big gay bar, you do not want to go any further than that. The gay bar is at the limit of the safe zone.
Blues bars are big on Bourbon Street. Most people think "jazz" when they think of The Big Easy and music. But the blues on Bourbon Street are where its really at. I've lost my ever loving mind listening to the blues on Bourbon Street drunk on...bourbon.
For breakfast, beignets at the Cafe Du Monde come highly recommended. Yum-yum-yummy! Fried dough with powdered sugar.
I hope you are not going to New Orleans during Mardi Gras. It is just a little too nuts then. Two weeks before Mardi Gras is just about right. But Bourbon Street is an impenetrable mob during Mardi Gras. Sure, the "show us your tits" ritual is fun, but it gets old fast. The parades on Canal Street are a sight to see, though.