[Skwiddz]

I would have to agree with SchwarZ22, Fushigi Yuugi is a really good adventure story with romance as the main theme.
Without giving away too many spoilers here is a breif summary of the story.
Middle school student Miaka Yūki is under a lot of pressure to pass the entrance exam for the competitive Jonan Academy. Her friends do not believe she will get in, but she is determined to because her best friend, Yui Hongo, has applied for the same school and she wants them both to go to the school together. While at the library one day, Miaka and Yui come into contact with a strange book there, known as The Universe of the Four Gods. As a result of reading this book, they are then transported into the novel's universe.
A very well done anime with 52 episodes and three OVA's and a manga spin off series, this is one of the best love stories.
Other good adventure/romance anime's would be
-Cardcaptor Sakura
-Sailor Moon
-DearS
-Kannazuki no Miko (although it is mostly yuri a very good story)
-All the other anime's mentioned.

I hope this helped =]