My fav saeguk drama are:
1. The Princess Man ( saranghae.. PSH)
2. The Queen Seon Deok (it makes me fall for Nam Gil )
3. Sungkyunkwan Scandal
4. Dong Yi
I'm amending my list.

A Tree W/Deep Roots
The Princess' Man
Chuno
Hong Gil Dong
Sungkyunkwan Scandal
Updating my list: 1. The Moon Embracing the Sun 2. A Tree With Deep Roots 3. The Princess' Man 4. The Legend
a jewel in the palace(my 1st historical drama) jumong a tree with deep roots dong yi yi san
The Princess' Man & The Moon That Embraces The Sun :)
Updating mine 1. Dae Jang Geum 2. Queen Seon Deok 3. Jumong 4. --------------------------reserve 5. The ) that Embraces the O 6. --------------------------reserve 7. The Princess Man 8. Dong Yi 100. Hwang Jini yet to finish DRT Iljimae Chuno Ps: there still some great ones that im lazy to watch because of humongous episodes!!
1. Moon-Sun 2. Iljimae 3. A Tree With Deep Roots 4. Hong Gil Dong 5. Chuno 6. Sungkyunkwan Scandal
Hwang Jin Yi Hong Gil-Dong Capital Scandal
dae jang geum and hwang jin yi
mine are: dae jang geum the princess's man sungkyunkwan scandal
1. The Princess' Man 2. Dong Yi 3. Faith 4. Hwang Jin Yi 5. Seo Dong Yo <3 6. Iljimae 7. A Tree With Deep Roots 8. Painter of the Wind And still watching and searching for more :D E. Had to edit it a bit :D I noticed that nobody mentioned Seo Dong Yo, I highly recommend it! ;D
My favorites are;

Jejoongwon
Queen Seon-deok
The Princess' Man
Capital Scandal
Dong yi
Kingdom of Wind

These are the best historical kdramas I've ever seen.

Mine would be a little long?:) Jewel in The Palace Queen Seon Deok - i love Bidam:) The Legend Sungkyunkwan Scandal Tree with Deep Roots Yi San The Princess' Man
1. Bridal Mask 2. Princess' Man 3. SUngkyunkwan Scandal 4. Hong Gil Dong
Must see...: <3 Queen Seon Duk The Legend Dong Yi Yi San A Tree With Deep Roots (Hangul birth :D ) Chuno The Return of Iljimae The Moon that Embraces the Sun