Greg Cox wrote:
TNG: "Genesis." C'mon, Barclay turns into a spider-monster. What's not to love?
TOS: "Gamesters of Triskelion." Even as a kid, I knew this one was corny and cliche, and Shawna's tin-foil bikini would embarrass Barbarella, but I still enjoy it occasionally, if I'm in the right frame of mind.
And I sometimes think I'm the only Trekkie in the world who always eagerly looked forward to "Catspaw." It's the one-and-only Star Trek Halloween Special for the Old Ones' sake--written by Robert Bloch, no less!
Genesis is the only Star Trek episode that made me want to hide behind the sofa with my eyes closed. My guilty pleasure is Spock's Brain.