Student Exchange Programs

i am going to study abroad as a junior in highschool for the spring semester. i am thinking about going to either ireland, spain, holland, or sweden. hav u ever been to any of these? if so was it a good experience? i speak english and alittle spanish i will hav taken two years of spanish. is dutch hard to learn? wich country would be the best european country to study in? has anyone had a bad experience as an exchange student? did everyone get along with thier host family? plz just giv me any info u hav about being an exchange student?