First of all, everyone's posts have been most helpful, thanks. Now for some more personalized advice:

A friend and I decided to drive cross-country this summer. We live in NJ but are actually flying to Jacksonville, FL for the Hertz drive out of Florida special (the $60 for 2 weeks rental more than pays for the airline tickets).

We have the car for 2 weeks, leaving from Jacksonville and having to drop it off in Salt Lake City 2 weeks later. We are going to drive north a bit to make a stop at Dollywood and Graceland in TN and then head West. I'd like some suggestions for things to see along the way. Once in Cali I have plans with friends (Price is Right!), but definitely need some suggestions for things along the way. Will I have time to make it to Seattle or should I cut that out and head straight to SLC from Cali (plan to spend 2-3 days in Cali.)

Let me know what other info you have, Thanks so much for all your help.

L