I like to stay at the beginning of Orchard Road which is more accessible by all means of transport, especially to River Valley, Chinatown, Little India and City Hall. There is also a bus #36 to Changi airport.
Preferred accomodation
*Hotel Rendezvous
4-star hotel. If you don’t like to walk to much, this is a nice location. Map
*Hangout Hotel
No Frills like Air Asia. Book online-it’s cheaper. Map
*YMCA Hostel
Youth hostel. Map