I've created a map on Google Maps to let the people know how much is far the Summit from the Hotel and how to get there (walking): http://is.gd/2zqdj

I've already been two times in Amsterdam and I can say the location of the hotel is very nice!

There's a train that takes you from the Schipol Airport to the Amsterdam's Train Station. Once you get out of the station the hotel is 100-200 meters on the right.

I confirm you can take the S103 bus to get to the Summit place so it's very well connected!

I'm going to get some notes I took when I stayed in Amsterdam so I'll be able to give you more tips about this beautiful city!