Sins of the Father, Redemption
, and The Way of the Warrior
all have to be included. Aside from that...
A Matter of Honor
, maybe. I like Tacking into the Wind
's Klingon parts, particularly Ezri's speech to Worf about how corrupt the Klingon Empire's become.
Does The House of Quark
count as a Klingon episode? If so, it's got to be on the list.