Olwen is one of my favorite Welsh names. I don't often get strong romantic or fanciful images from names, but Olwen makes me picture a beautiful woman in a long white dress, walking in the wet sand along the sea's edge, her long, wheat-colored hair blowing in the wind. It makes me wish I could paint.
Definitely Olwen, not Olwyn. That -wyn ending is so masculine...it ruins the name for me.