Hi Printer
I love my home city and really wish you would consider staying in Singapore. But it does seem that you'll enjoy yourself better on one of the Malaysian islands. And you've come at the best time for snorkeling and diving (but also the peak season).
The main island for chilling out during this time is Pulau Tioman. You may fly or take the bus-boat journey. The details are a bit tedious to write here but if you are browsing in the bookshop, look at page 187 of the current Lonely Planet Singapore City Guide.
Fly:
http://berjaya-air.com/index.htm
Bus:
Transnational +602 - 62947034
Check this site for details of transport options:
http://www.tioman.com.my/
You may want to just book a free-and-easy tour with a travel agent in Singapore and save yourself the hassle of working the trip out.
When I was last there, the waters were pristine. You may spot some dolphins on the boat ride there. The island is also good for some forest trekking. My guide even took us mouse-deer spotting in the night, but we didn't see any. I just wonder if they have been hunted to extinction by now.
Having said this, there are also many other islands on the east coast. But Tioman is the most accessible.
Have a good vacation.
Edited by: GabrielTan