Which of these US States is the best (for a journey!!!)?

I would choose Chicago, Illinois (right smack in the middle of the country), if I were visiting America for the first time. New York and Los Angeles are two extremely different cities. Chicago is more "typical", but still an exciting place to be. However, I recommend visiting in the warmer months (June-August). It's way too cold to visit in the winter. They have a huge film festival in October.

I wouldn't try to visit a state. They're too big. America is too big. I'm afraid you're going to have to narrow it down a bit, unless you have a few months.

Michigan for it's thousands of square miles of forested, wilderness in the U.P. You'll never find a better place to get lost if that's your thing.

Well, it depends, are you looking for something representative of the United States, or a really fun place (that will still be more similar to most of the United States than even Britain)?

Hawaii. Las Vegas (Nevada). Orlando, Disney World (Florida). New York City. Hollywood, LA beaches (California). These are all great places for having a great time, depending on your tastes.

Stay the hell away from the midwest. Anything from Idaho to Arkansas to Wisconsin and back to Idaho (and everything in between, look at a map) is pretty damn boring.

Of course, answering this question is entirely contingent on knowing more about your interests and travel objectives. Are you looking for scenery/outdoor exploration, culturally significant landmarks, exciting nightlife...all of the above? Other stuff? Tell me more and I'll be happy to add my two cents.