I was a first-time flyer myself (a very fearful one, may I add) last year & had a wonderful experience. I used Southwest Airlines. You get free drinks & snacks. And if you get their 'Business' ticket (which isn't a whole lot more than the regular ticket & you get to board first so you get your pick of the seats), you also get free alcoholic drinks (which can help with your jitters, lol)
Can't tell you about non-US airlines, but for a domestic flight...
1. Southwest is good because of the laid back atmosphere on board (friendlier pilots and flight attendants), the free snacks and drinks, and the lack of stupid fees (checking bags, etc.).
2. Jet Blue is nice because of the free satellite TV on the back of each seat (takes your mind off the flight). Also, their planes are quite new.
3. I would avoid Northwest Airlines if your flight is a relatively short one. They still have a few dozen DC-9s in their fleet, and they are well over 30 years old. If you are a first time flier and are nervous, you should avoid having to worry about flying in a plane that is too old.
It depends on where you are going. Within the US, JetBlue, Virgin America, Southwest are all good.
(in no particular order)
Asian: Singapore, Cathay Pacific, Japan Airlines, All Nippon Airways, Asiana, EVA Airlines, Qantas.
European: Air France, British Airways, Lufthansa, Virgin Atlantic
Middle East carriers: Emirates, Qatar
For domestic travel I like Delta, Virgin, Jet Blue and Southwest
For International travel I prefer - Emirates, Qatar, Cathay Pacific.
It also depends on your budget but these are my preferences. Remember to bring your own food/drink and headphones as most airlines charge ridiculous amount of money ($5 for headset; $9 sandwich)
All the airlines are about the same. They treat you like cattle, jam you into a seat that probably doesn't work and probably over book the flight.
Go for the cheapest fare you can get.
I personally like Continental the best, nice seats, good food, comfortable trip.
I flew Delta my first time, I really liked it, but they have really gone downhill lately.
It really doesnt make much of a difference they are all about the same. Equally rude and incompetent.
Just go with whatever gets you the best deal.