the above posters are right. stay away from the popluar commercial places like ko samuai and the other notorious islands. I stayed on an island called ko chang-its a couple of hours boat ride out of bangkok as far as i remeber. it was heaven. had to be dragged away after a month.
the quiter islands are cleaner, quiter, probably safer??, friendly locals and still have plenty of places to eat and drink.
Beach huts-basic but very clean-9 ft away from clean turquoise water. Bliss.
Best of luck.
ps i love bangkok, been there lots of times but is five nights a bit much?
killter