The good thing about NOLA is you can get around most of the interesting places
sans car. You can take cabs, streetcars, buses, carriage rides, and shoe-leather express. Here is a site to explore:
http://www.experienceneworleans.com/If Jazz is you thing, we have
JazzFest which is two weekends, the last weekend of April and the first weekend of May. There are many jazz spots in the city, best thing to do is get here and ask locals for some good places which may not be in the "touristy" areas.
Our second tourist season kicks off this weekend (Southern Decadence...think GAY Mardi Gras) and will last until Halloween, which is the fifth largest event in NOLA and is a really good time. Also, check around at many hotels because some have really good offers for particular weekends and there are some really nice bed and breakfasts and smaller hotels which have GREAT deals but aren't on the beaten path, these are good if you plan to stay awhile and want to have fun, but when the time is needed really want to be able to rest, I suggest those as an option because the French Quarter doesn't sleep.
As a former Bourbon Street bartender, stay away from Pat O's hurricanes...trust me! There are better ones to be found.
PS...check out
House of Blues - New Orleans