There's the Airport Hilton, but don't know if you can get it for under $200. There are a # of hotels near the Central Train Station in a variety of price ranges. You might want to check Travelocity or Expedia for your date.

If they stay downtown or want to get downtown from airport, obviously the train goes. Once there, they can walk or tram to areas like Dam Square or Leidesplain (the latter would require a tram).

It's kind of touristy, but taking the canal boat tours is good for a first time visit. Cheers.