I am trying to drive from austin texas to Eugene oregon and stop in Grand Canyon, Las Vegas, LA, San Fran, Eugene and then back. I can leave austin as early as 9/26th and would like to be in Las Vegas by sept 30th. I would then like to get to San Fran by Oct 3 or 4 and explore san fran until Oct 14 (I am meeting friends there) and then head to Eugene on Oct 14th.

I have never really driven by myself and am trying to figure out the following:
1. What route is the best to take so I don't get too tired and still see things?
2. Is there a way to guesstimate the gas costs and compare that to flying?
3. How long should I plan for the trip?
4. What is the best order to see the sites in? How long to spend at the grand canyon?

Thanks for any information you can provide. Am also not opposed to sharing some of the trip if anyone is interested...