If money is no object, have a meal in Petronas Towers restaurant. Or if you like street food, try some satay or take a stroll along Chinatown (locals call it Chee Cheong Kai/Petaling St) and sample the food. At night, the street is cramped with hawkers and food stalls and is quite an experience. But hang on to your wallet/handbag and don't let down your guard. You will be badgered to sit down and eat but walk through the whole length first and have a good look before you decide. Bintang Walk is also interesting and more relaxing. Have a drink there at some cafe broadwalk.
Check this out:
http://www.youtube.com/watch?v=anegVgRmj…
Don't waste your time with a Vietnamese restaurant in Malaysia! If you want to eat Vietnamese, go to Hanoi. That restaurant is for Malaysians who can't get to Vietnam.