I'd suggest: - Million Dollar Highway in Colorado - Black Hills in South Dakota - Glacier National Park in Montana - Most anything in Southern Utah - Grand Canyon - Yosemite in California - Joshua Tree in California - Crater Lake Oregon - Snake River in Idaho - Yellowstone in Wyoming - Hana Highway in Maui, oh wait, you can't drive there from here...
You prolly won't be able to fit all of these in one trip, but it's good to have choices.