Zettai Reido is good, because it involved crime solving.
Juui Dolittle is good too, because the story is about animals care, and they make it very interesting.
akuma to keiyaku shita onna (guilty) is one of the best Jdrama I ever watched!! It keep me wanting more and more and the suspension was killing me to finish it in one goal.
although it been many years, but Kou Kou Kyoushi 2003 is a very good drama, about teacher and student's love. Very interesting drama to watch.