June - Nov are given as the general period for hurricanes. Some info on 2005 seasons landfalls here:
http://en.wikipedia.org/wiki/2005_Atlantic_hur ricane_season_statistics which demonstrates that '05 affected the north of the Caribbean more than the southerly island groups. But '06 may be different . . .
This northern and western problem is generally the case anyway as the storms move right to left towards the US / Mexico coast. No specific place in the Caribbean is immune to hurricanes though.
If you are worried, consider the further south such as Trindad / Tobago, or Curacao, Bonaire, etc - but some of these islands are quite arid and not as 'green' as those further north.
The other option is to go east - as the storms begin in the east, they have less energy as hurricanes gain strength as they travel over warm water, so if you look at Guadaloupe, Barbados or Dominica for example these will be less prone to substantial damage - but can still be affected .