I've done both too, lived in each for a year or so, and would definitely do Europe. I found it much more interesting and a bit more of a contrast i think. The USA is definitely different but I feel like we get so much exposure to the USA in TV and movies that I felt like it was much more familiar. The food is a million times better in Europe too!

Either would be good if you haven't been, but I don't plan on going back to the USA in a hurry. Parts of Europe on the other hand has many more places I'd like to go. obviously in two weeks you won't see everything but you could pick a country or two and have a blast.

Although you mention Alaska, I'd love to do a trip to Alaska...... or South America.