The ones I think don't do you justice are - The first one in implied nude, on some stairs, the angle does your bottom no favours at all. The one in the lily pond with your arms outstretched, you just look uncomfortable. The fantasy Medussa one doesn't work for me either. I also think you have too many of you kicking, perhaps cut them down to two at most.
The definite keeps are - Your main image You in the window In the pond showing half a bottom The two by Garethc976 are really nice the last one in your sport section is really good the first one in your fantasy section holding a sword.
The rest I can take them or leave them. I hope that helps, but do bear in mind that the most important opinion of them is yours. If you like them, you should keep them. Its a good decent portfolio and shows variety.