Amsterdam has been my favorite city since my first visit there in 1993. It is a friendly place (most of the people speak at least some English). There is so much to see and do, ie.:
The State Museum (Rijksmuseum), the Van Gogh Museum, the Ann Frank House, the diamond district, and the famous Red Light District.
Near the Red Light District is the Church of our Lord in the Attic, a series of 17th century townhouses, which a full scale church in their shared attics - catholics worshiped there during the Reformation, it was pretty much an open secret at the time.
Many small streets spread out from the Leidesplein and are lined with restaurants of almost every ethnicity imaginable.
Don't leave without sampling a Dutch Pancake (wafer thin with choices of ingredients).
Getting about town by Tram is a snap - they seem to run everywhere, and most of the tram lines converge on the Central Station.