Could y'all at least page me when topics like this come up?

I'm Qantas Gold and United Premier. I travel between SYD-SFO about 7 times/year and I've been to PER twice. And DFW - well, duh?
First of all, for the trip you're planning, you want to be on Qantas. You DO NOT want to be on United. The suggestion of Air New Zealand was nice and of course SQ is one of the best airlines going.
Here's the play-by-play for doing the trip you're doing.
- Leave DFW in the afternoon and have a few hour layover at LAX. Try to be as tired as possible before you start your trip.
- Get some food at LAX and pound 4 drinks (beer works for me).
- Crash out before takeoff and for the first hour of the 14 hour flight.
- About 90 minutes after takeoff, they'll come by and serve you dinner. Eat it unless you gorged yourself at LAX.
These days all the SYD flights leave from Tom Bradley International Terminal which doesn't have much to offer for food. That reminds me, when you're connecting on American via Terminal 4, there is a Chili's and I think a Baja Fresh there. So some decent eats on the secure side. To save yourself some time, don't leave the secured area, instead, take the shuttle from gate 44 over to the TBIT. When you go down the escalator, DO NOT head left towards baggage claim, head right into what looks like a little room. That's where the shuttle bus picks you up.
Now, it just occurred to me that since I don't know what flight you're on, I probably should have asked that. You've got 3 options from DFW.
- QF8 "direct" from DFW via BNE on a 747
- QF12 - nonstop on an Airbus A380
- QF108 - nonstop on a 747, continuing service from JFK
So... I've flown Premium Economy and Business Class on the QF 747s. I've only flown Economy on the A380 and obviously I've spent boatloads of time in Economy on the 747.
I usually come home to Sydney on a Friday night after a work week in The Bay Area. That flight is usually chockers (FULL). Once or twice, I've been able to fly home to SYD on a Sunday night or a Tuesday night. Those flights are usually only 2/3rds full. If you're picking economy seats, here's what you need to know.
On the 747s, sometimes the screens will be smaller but most of the ones used on the LAX-SYD run have been retrofitted with the same seats as the A380. The A380 has nice seats with a really big screen. On all the Qantas International flights, you've got personal entertainment with plenty of movie options, music options, TV options, etc.
Also, on the A380 and the retrofitted 747s, you've got snack bars halfway down the aircraft and at the rear of the aircraft. I think it was defroach that alluded to picking the seats near the rear of the aircraft where it's only 2-4-2 instead of 3-4-3. There are about 3 rows of the 2 seats on the outside. Whatever you do DO NOT pick a bulkhead seat. There's nowhere to store your stuff.
Now that reminds me, another thing to consider is Aisle or Window. Since I was a little kid, I have always been a Window seat guy. This is a 14 hour flight with 13:45 over featureless water and clouds. I strongly recommend the Aisle. About 18 months ago, I got stuck in a Window seat for 9 1/2 hours before I could get up and go to the toilet. This was after I pounded 4 beers at LAX so I was dying by the time I got there. I've been an Aisle seat guy ever since.

OK, so we're in the air, and we've eaten dinner at 1 am LA time. Now, try to watch a couple of movies. You don't have to do four but watch 2 or 3. You have enough time if you want to watch all 3 Godfather movies back-to-back-to-back, you can. But, when you get there, all you'll think about is Eye-Talians killing each other. I recommend you check out some of the Australiana content like "Housos versus Authority" (That's Un-Australian Mate!). That reminds me of another warning, Qantas will have movies with topless ladies uncensored. When I was watching Housos and there was a bedroom scene, I was like - whoa. Might have to get that one on DVD.

So by now, you've watched a movie or two, it's OK to go ahead and crash now. Try to sleep for 2-3-4 hours or so. 6 hours is nice if you can do it. You did spring for the $300 BOSE headphones with the 14 hour battery life right? I've gotten as much as 25 hours out of the battery on my BOSE headphones before. That reminds me, for sleeping, I like to turn on some music like "Reelin' in the Years" (a countdown of hit music from each year starting with 1950 or so). I usually plug in anything between 1980 and 1995 and crash. The background noise is better than nothing.
So, now you've slept a little bit and you're semi-awake. Look at the Flight Path and see how much longer before you get there. They'll serve breakfast about 90 minutes out from SYD. I like to start a movie with about 2:30 left in the flight and then read a book after the movie ends until we get there. Also, don't forget to bring your Passport and a pen when you get to your seat. You'll want to take that time to fill out the customs declaration.
You land in SYD and have to clear Immigration, Claim your bag and clear Customs before heading over to PER.
Depending what time you arrive, it can be pandemonium at Immigration. There are lots of flights from the US and Asia that arrive about the same time in the morning.
Now Perth is a 4 hour flight and you'll have to change Terminals to get there. That flight will usually be on a 737 or better. I've flown it on an A330, a 767 and a 747. So, your entertainment options will vary. 767s still have the screen at the front of the cabin and the Domestic 747s have small screens in the seat.
Here's the deal, there's a 2 hour time difference between SYD and PER. My normal recommendation is that for people staying in SYD, you MUST stay awake until at least 9pm in order to help get over the jetlag. For going to W.A., you're going to want to stay away until 9pm as well but... you'll probably want to sleep an hour or two on the flight across from SYD.
Now that you know more than you ever wanted to know, back to part of your original question.
Making that trip in Business Class versus Economy is a no brainer. Really. I don't know if this is an option for you but on Qantas, Premium Economy is about as good as Business Class on other airlines like United for example.
Let me know if you need recommendations for the return trip.
While you're in Perth, I recommend heading down to "Freo" (Freemantle) and going to the Little Creatures Brewery.
Good Luck!
[This message has been edited by HollywoodBQ (edited 2/18/2013 6:55a).]