Huh... no one recomended Giant or Salaryman yet? people tend to forget about those, but they are the top dramas. Definately worth watching
Giant is more of a serious, but very deep drama. Its about 50 or more eps long, but you totally forget about the lenght after a few eps. It has some interesting romance (mature yet fragile) with more then one pairing. And it shows a longer period of time as the main cast grows older and stronger. Its really amazing story of three siblings who lost each other but were able to find themselfs again.
Salaryman is pretty funny one with great acting and also interesting love themes. Perfect if you just want to laught your ass off :D
Oh... and REAAALY good dramas are also Shut up Family or unexpected you ^^