Help! USA Itinerary = sucks

[cattlikewoah]

Hey... so I've posted in the USA specific threads about my travel plans and now I've come to a point where I have to choose from 2 itineraries...

My friend is a travel agent and has quit so I have a week to book tickets etc. so I can get them at cost price.

The 2 options are:

SYD dep 9.20pm arr Honolulu 10.10am (approx 10hr flight)
HNL is just a transit stop but I have the choice of a 5 hour stop or a 12 hour stop.

I thought if I can get out of the airport, I'd do the 12 hour stop because after 10 hours on a plane, I'd like to walk around etc.

Does anyone know if I can get out of the airport (seeing as its an international flight I'm taking?). I'd have to go through customs etc right?

The 5 hour stop over then takes me to Minneapolis (also transit) then to Memphis which is technically our first stop. Total travel & waiting time from Sydney to Memphis TN is 27.5 hours.

The 12 hour stop over takes me to LA (transit) then to Las Vegas as the alternative first stop (and we would scrap Memphis all together). Total travel & waiting time from Sydney to Las Vegas is 33.5 hours. There would be 5 hours waiting in LAX too...

The next stop is Austin Texas and is cheaper if I flew out from Nashville TN (instead of Memphis) or Las Vegas.

So a few things I want opinions on:

1) Memphis vs. Las Vegas
2) 12 hour waiting (where we *might* be able to get out of the airport) vs. 5 hour waiting in Honolulu

What would you do?
What would be more interesting - we'd like to see the bright lights of Las Vegas etc. and check out Graceland in Memphis... but we'd that would be the most touristy thing we'd do, and it would only be for about 3 days or so.

Any help ASAP would be

Thx
Steph