If you're planning to travel far across the city, don't take a cyclo-cab as most of the drivers don't speak English and will misunderstand directions if it's an unfamiliar destination.
Ride in a cyclo at least once. Hanoi's traffic looks chaotic from the pavement, but up close there is a certain rhythm and symmetry to the flow of cars, motorbikes, cyclos and bicycles. They're very cheap too - you can go just about anywhere in central Hanoi for less than US$1 (HK$7.78) - but be sure to negotiate the fare in advance.
The colonial Sofitel Metropole Hanoi is one of the city's top hotels with lots of history and charm. It's centrally located and only a short walk or taxi ride to the main shopping areas. Many famous people have stayed there since it opened in 1901 - Charlie Chaplin (who visited with Paulette Goddard on their honeymoon), Graham Greene and Somerset Maugham to name a few. Jane Fonda and Joan Baez could be found in the hotel's bunker during air raids during the Vietnam War (15 Ngo Quyen Street. Tel:  826 6919; www.sofitel.com).
The five-star Melia Hanoi in the centre of town is one of the top Western-style hotels. There's even a heliport on the roof, the only one in Hanoi (44B Ly Thuong Kiet Street. Tel:  934 3343).
Enjoy a head massage at one of the many street-front hair salons. Shampoo is massaged into your dry hair for 30 minutes, then it's washed and dried, all for less than HK$10, which has to be the best bargain around. You don't need to know how to speak Vietnamese, just use sign language. The towels and combs have seen better days, though, so you might want to bring your own.
Make sure you go to the Old Quarter, a maze of 36 streets all named after different trades, Bamboo Basket Street for example, and all lined with tamarind trees.
Where Trong Thi Street meets Trang Tien Street, at the south end of Hoan Kiem Lake in central Hanoi, you'll find a variety of shops selling the excellent Vietnamese lacquerware that costs a fortune in shops such as Tequila Kola and Banyan Tree.
My No 1 recommendation in Hanoi is the Thuy Ta Cafe in the northwest corner of Hoan Kiem Lake in the Old Quarter. It's remarkably well-shielded from the traffic noise so you can snack and sip a coffee or beer while enjoying the serenity of the lake. We spent several hours at a lakeside table on our first day in Hanoi and enjoyed it so much we went back there for our last few hours in the city (1 Le Thai To Street.
Tel:  828 8148).
There are too many excellent restaurants in Hanoi to count. At Gustave's near to the Opera House, a French bistro and restaurant, you can sit in overstuffed chairs and treat yourself to crepes suzette and listen to live jazz in the evenings. The excellent restaurant upstairs is a hangout for trendy locals and expats, with tables laid with linen and silver (17 Trang Tien Street. Tel:  825 0625).
The Press Club, opposite the Sofitel Metropole, serves an excellent dinner on its open-air balcony. Reservations are essential (59A Ly Thai To Street. Tel:  934 0888; www.hanoi-pressclub.com).
Seasons of Hanoi is set in an old courtyard house where you can sample Vietnamese food either outside or inside. There's a pianist and violinist playing a selection of Bach and Mozart and the food is excellent. The spring rolls are to die for (95B Quan Thanh Street. Tel:  843 5444).
Great places to eat are Cha Ca La Vong where the speciality is cha ca, fish cooked in a hotpot with dill and noodles (14 Cha Ca. Tel:  825 3929), and Indochine in a charming old villa-style house with an interior courtyard. Try the banana flower salad (16 Nam Ngu. Tel:  824 6097).
The Emperor Restaurant, set in a courtyard house, serves excellent Vietnamese food. It's a 10-15 minute walk from the Sofitel Metropole, past the Opera House and Hilton Hotel (18b Le Thanh Tong Street. Tel:  826 8801).
If you have more than three days in Hanoi, make a trip to Halong Bay and spend the night on a boat in the bay. The boats aren't luxurious (no morning shower), but reasonably comfortable and we had a great time sharing stories and drinks with new friends on the deck at night, and then seeing the sheer rock walls reappear in the dawn light. Bring your own wine as it's four times more expensive than in Hanoi. Handspan Travel (www.handspan.com) pioneered this night-on-a-boat concept but now a number of travel agencies offer it.
Bring US dollars in small denominations. Although all the shops and restaurants accept US dollars, change is usually in local dong. Travellers cheques tend to be cashed in dong too.
Keep a perspective on money and bargaining. Meals, transport, souvenirs - just about everything is cheap in Hanoi by Hong Kong standards and though you may be tempted to bargain to the very last dong, bear in mind that that last dong means a lot more to the Vietnamese than it does to you. We paid a cyclo driver three times the going rate for a ride back to our hotel (US$3 instead of US$1) and were chagrined until we realised we had probably made his day.