I'm not going to list all the episodes he directed here, just some of my favorites, or episodes that stand out as well directed (even if the story isn't fantastic)
TNG:
"Where Silence Has Lease" I love this episode. Pacing is so important in directing (and editing) and - usually - the faster the better... but a story like this, which serves as a microcosm of the unknown aspects of space and the large distances therein - benefits from a slow, deliberate pace. This was a limiting bottle show for Kolbe, and he had fight the claustrophobia of the script and limited sets. He succeeded hands-down, because once this episode gets going, I can't turn it off. Not perfect, but, certainly a great showing.
"Darmok" Perfect performances, and staging of the action and dialogue scenes, and he allowed the actors to really sink their teeth into this. The location photography is top notch. You'd never suspect that the confrontation between Picard and Dathon happened within eye-site of the Hollywood sign.
"All Good Things.." Fantastic, considering the multiple timelines, and the technobabble nature of the story, the ensemble has rarely come together as they do here, and they shine even more sleekly than big D herself in all three timelines. The last scene is particularly well-staged.
DS9
Our Man Bashir - Man does this guy know how to do Bond better than a lot of Bond directors? A case could be made. I like the fact that he knows that its important to let the cast go a bit over-the-top here... otherwise he might have been picked to direct Bond lol.
"Blood Oath"
"Through The Looking Glass"
"The Siege of AR-558" All three of these are standout action episodes that are done in a style that is more ambitious than anything in TNG. At no point are the characters forgotten amidst the mayhem. TTLG is particularity inspired romp that really reminds us of the excitement of the Cloud City scenes in Empire Strikes Back, with big gun battles in the hallways. BO is like a fantastic Dungeons and Dragons type adventure with Klingons! And "Siege" is just fantastic..
VOY
Caretaker - directing any pilot is hard, and he makes it work. I think he really brings out the best in the series. I think he also directed Ethan Phillips better than anyone.. Neelix had more shades to him here, surprise, moral ambiguity, secrecy, humor, than in any other episode.
"Eye of the Needle" A great little episode. The directing is very professional.. done with a sure hand. I particualy think he directing Wang to his second-best performance as Kim here. (Wang's best was "Timeless")
ENT
"Silent Enemy" I just watched this one and I liked it a lot. I particularity loved the camera placement in the Tucker/Reed scene, so you know the space is very cramped.