See the USA in a week / month / ...?

Spokey,

Not sure if you've done the drive already, but I bet by just hitting Chicago, Grand Canyon, Route 66 (in Arizona or NM or Oklahoma) you could do it in under 2 weeks, even including stopping up in Seattle and Roswell, assuming what I infer is correct (that you don't plan to stay anywhere for long except Seattle). That's a pretty good clip, however, and one that may require a 2nd drive.

Chicago is a necessity anyway as it's the only way to get to/from Indiana and Wisconsin.

If you want, I can give you the route I took when I did something similar two years ago (May 2003).

Bob, I agree that mid-Sept and October is probably the best time to go, but there are fires in the West at those times, and a freak storm (such as what hit Denver last week, granted it was mid October) could strand you in the mountains. Late May is probably the first time you can go and guarantee no snow below 8000 feet. Any later and you're in the peak of the heat and that is not fun (for me, I'm a wimp when it comes to heat. That's probably why I live by the Great Lakes)

Hope this helps, Spokey.