I've got fond memories of
Klingon Honor Guard too, probably because it was the first
Unreal engine game I ever played (it was years before I ever got around to actually playing
Unreal itself!). I remember liking it at the time, the level designs were pretty good. I remember one level was actually inside the Rura Penthe prison complex from STVI.
Another one I remember vaguely is
Starfleet Academy for the PC (not the console version). It was one of those games riding on the coat-tails of the multimedia boom in the wake of CD-ROMs, and while I appreciated its aims, I think a lot of the acting in the full motion video sequences was sub-par. Unfortunately.