Jet lag is not so bad when going to South America because they are in the same time zone as part of the US (depending on the country and where in the US).

Some people like Rio de Janiero. I enjoyed Chile but some may find it boring.

I think you are limited to South America, US, Caribbean, and major Western European cities (go too far or too small and it takes half a day or so to get there, eatting up time).

Go to a bookstore and look at the travel books. If you see a place you like, buy the book and go there. Online, there are many travel sites, including www.virtualtourist.com , www.fodors.com , www.lonelyplanet.com and many others.