The entire run of the original series!
TNG- Borg stuff, Final episode, yesterdays Enterprise and all the guest stars by Scotty, Sarek, Spock and McCoy.
DS9- The Visitor, Trials and Tribble-ations, the entire Federation/Dominon war, the final episode.
TMP- Kirk's first sight of the refitted Enterprise. While Goldsmith's magnificent score plays.
WOK- Spock telling Kirk he has no business being anything other than a Starship Captain, Kirk's awesome reply to Khan's request, (Audiences cheered in the theater when I saw this) Spock's death.
TSFS- Kirk's reply to Sarek when he askes him, why? he says, "If I hadn't it would have been my soul." Kirk's tricking of the klingon stooges by luring them over moments before Enterprise goes BOOM.
TVH- The final scene when the crew see a brand new Enterprise waiting for them.
TFF- Kirk has a great line. "I lost a brother once. I was lucky to get him back." The pain scens are great.
TUC- Spocks line, "Only Nixon can go to China."
STG- The entire opening act with Kirk's premature death. Saucer crash and Picards arc. Despite its holes, the flick holds up really well.
FC- Picard and Lilly's stuff. The opening space battle is good stuff too, although too short.
The rest can go screw.