Well, Dallas Rain is a good source for where to stay--she likes Lower Garden along St. Charles. It is nice & there are several nice hotels there, but not a ton of them & they book fast.
You'd do better in the Central Business District (aka "CBD"). Lots of places to stay there & on the fringes of the French Qtr. as well. I will warn you: New Orleans (aka "NOLA") is NOT an easy city to find a hotel room @ the last minute, ESPECIALLY prior to Mardi Gras. It's also a ridiculously-expensive hotel city, compared to west of the Mississippi. There are deals to be had but you must be aggressive & savvy on hotels.com & other websites (which I'm not).
Kenner is a good suggestion--locals, even in NOLA proper--like it for ease of access & the ability to park. Metairie also has its fans for the same reason. Those are both just west of New Orleans itself. Then there's NOLA proper in the Fr. Qtr., CBD, or Lower Garden. Thou SHALT NOT stay in Mid-City! Despite the fact I live in Mid-City & love my neighborhood, the only hotels in Mid-City are scary-ass-nasty-places on Tulane Ave. Not ideal.
I'd also recommend against your staying in NOLA-East. While after you've been here several times it would probably be OK once you had checked everything out & knew where to go & where not to go, it's a lot to ask of someone brand-new to the city. You could stay on the Westbank in a couple of areas but like NOLA-East it's a little bit nuanced for a newbie unless you have specific recommendations from a local girl who KNOWS the area. Same for Gentilly (one neighborhood closer to the CBD from NOLA-East), although there are a couple of places in Gentilly before the high-rise that I've thought were all right despite being cheap motels--the Econo-lodge there actually has to be the nicest Econo-lodge I've ever been to. It's still an Econo-lodge.
Your best bet is a CBD hotel offering a post-Mardi Gras special which will get people who are walking downtown over (tourists & those of us who work downtown), or a decent place in Metairie or Kenner which is convenient for the locals (since one problem w/seeing girls in the CBD or worse, Fr. Qtr. is no damn place to park).
I hope you do come visit NOLA & have a great time!