I've been to Mardi Gras multiple times. I prefer going earlier in the festival (i.e. Bacchus is the Sunday before Fat Tuesday) rather than right at the end. In fact, I'll be there in a few weeks to partake in some of the earlier festivities.
The weekend that you are talking about (in this case first weekend of March) is pretty insane (I've been that weekend twice). Flight/hotels/restaurant booking will all be pretty outrageous, so if you don't already have those....good luck. The Quarter is NUTS that weekend. I'd actually steer clear of it (or at least steer clear of Bourbon St). Just a mass of people (think the worst crowd control you've ever seen at a sporting event or concert). Sometime you don't get to pick which direction to walk because the crowd is just pushing you.
Alternative areas that will be less insane (but still very crowded) are Frenchmen Street (two blocks of bars all with live music), and a few blocks of the CDB (e.g. there's a strip on Tchoupitoulas that has some good bars) or you can head uptown (there's some good stuff on Magazine in the Upper Garden District/Irish Channel neighborhoods).
I'm not a big parade fan -- some of the HS marching bands are pretty good and some of the floats are creative (although less so in the bigger parades; but there are smaller parades that are pet themed or Star Wars themed or NC17 themed). Getting a good spot to watch is tricky -- people basically tailgate in "their" spot many hours before the parade (lawn chairs, coolers, etc). If you are doing that, suggest finding somewhere that is nearish to a bar, so when you have to use the restroom, you can go in, use the facilities (buy a beer to go of course) and then head back to your spot. If $$ are not object, you can look into ticketed seating on grandstands or balconies. I've never done that but it's a thing. What would be awesome is if your friend knew someone having a house party along the parade route and could get you an invite (would likely have to show up with booze and maybe some food to share). That way you have a built in home base (with restroom) and would be fighting the entire masses of humanity along the parade route. I had the opportunity one year and it was the best experience I had at a parade.
And of course be safe in crowds (pickpockets) and in talking to random people on the street (google "common street scams" before going).
Please report back if you end up going!
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