Some of their biggest/my favs:

Balloon
Hug
O
Wrong Number
Why Did I Fall In Love With You
Mirotic
Purple Line
Break Out
Love In The Ice
Hey! Don't Bring Me Down
Survivor
Triangle

The group was known for harmonizing, one of few male groups where every member is capable of singing and doing so well at that. Yunho was, and still is, the leader of DBSK, despite being the second oldest. The chemistry these five boys had both on and off camera was striking to say the least, forming a tightly knit friendship which they themselves to be crucial in life. DBSK appeared on dozens of TV shows and dramas alike, sometimes even making their own spin off dramas which are quite comical. Truthfully they are known to be good at everything, always prevailing over the challenges they were faced with. The five members of DBSK always pushed themselves until they were sick or worst, known as one of the hardest working and most poorly treated quintets in SM entertainment. If you watch any of their programs you will see how well they all get along, and their live performances are perfectly pitched and in sync.