If you come to Sapa you do have to do some excursions. There are three possibilities. You can do the excursions on a four wheeled vehicle, on a rented motorbike and on foot.
Sapa is such a colourful town thanks to the H'mong and Dzao people from the local hill tribes who head into the town's market every day to trade their produce. There's a main market every Saturday when the place is packed but there's a lower key one every other day during the week.
While visiting the region of Sapa you will take many photos. Something you should remember is that local people are not here to entertain you. They are real people living their daily lives. Ask always for permission when taking portraits.
For the ones really fit, I recommend the three day trekking to the Fan Si Pan mountain.
Despite its commercialization during the last seven years, Sapa is still a must-see on any northern Vietnam itinerary. On a clear day you will treated to views of steeply terraced rice fields, towering verdant ridgelines, primitive mud-thatched villages, raging rivers and astounding waterfalls.
The offer of places to eat in Sapa is quite varied. It won't be difficult to find a place that suits your tastes. On the walk from your hotel to the market you will see many restaurants. Prices are somewhat more expensive than in the rest of Vietnam, but still a real bargain.