dont forget to check out
http://www.boracaywindsurfing.com/ as to the place to stay, there are lots of choices at the white beach (the main beach) from the luxurious ones (located at station 1) to the economical huts (station 3)
i just learned from the owner of greenyard that this southwest monsoon is very unpredictable. one russian group stayed there for 28 days and only one! (1) decent day with good winds. tsk tsk so, your best bet with be the northeastern monsoon which should kick up probably in november.
sea urchins are not bad because they are not agressive. they only hurt if you stomp on them so that's the time that they'll hurt you back

seriously though, the kind at boracay are those that arent so "pointy". Ive seen much much worse.