I have to thank you for all your help so that I can enjoy my family vacation at Singapore. Please find some of my below comments which may help other as well.
1). Taxi -- For a family of 6 (3 adults & 3 small kids), I have no problem to take one taxi throughout the whole trip. All taxi drivers allows all of us in a taxi.
2). Jurong Swimming Complex is really very nice and cheap too.
3). IMM shopping mall is less crowded with free shuttle to and from MRT station and have an indoor children playground. Very children friendly.
4). The food at Lau Pat Sa Food center is a bit disappointed. Not really good at all.
Maxwell food center offers much better food.My friend told me that there is a good food center at Amoy street but I don't have a chance to try it.
5). Singapore zoo is great as always. (unlimted tram ride on weekday which is convenient.)
6). The location of Le Grove Apartment is a bit far & hot to walk but the living environment & facilities (except there is no business center) is better than Lanson Place. There is also a hourly free shuttle to Orchard road 7 days a week. Taxi fare to Orchard road from the apartment is just about 3-4 Singapore dollars.