Ann Frank House is a must visit; traveling by bicycle or at least a bike tour; Rijsttafel and Dutch pancakes.
FYI, you now need a reservation to go to the Anne Frank House. Make sure you prepare well in advance, otherwise you won't get in.
I work for a Dutch company and have been 50ish times over the last 10 years, so I can offer a bit of guidance.
For rijsttafel, I think the best a place called Blauw near the Vondelpark. Sorry, but I have to disagree with Bamaman on the Argentine steakhouses. I have found them targeted for tourist and average, at best. But, of course YMMV. For a really good place with decent cut of beef (I always get Biefstuk Bali, with a spicy sauce) among other items is a very Dutch place called Loetje. There are now a few locations, but the original one is behind and near the Rijks. For a hole in wall, bar atmosphere, with great spare ribs and an even better lamb shank, go to de Klos a few streets from the Leidseplein. For excellent Italian, go to Casa di David on the Singel. Best frites in the city is a place called Vlaams Friteshuis Vleminckx, which is down a small sidestreet not far from the flowermarket. For a great whiskey bar with over 2000 bottles, go to L&B, also down a side street near the Leidseplein. Don't eat anywhere on or immediate off the Leiseplein, its very touristy and not very good food. There is a good beer bar called Gollem that has a few locations throughout the city.
Hotels - All of the NHs in the city are decently priced and most have been recently renovated. Also Hotel Estherea is a nice boutique on the Singel.
Hope this helps. Any other questions, let me know.