Season 1: Episode 21: Kim Just Wants to Have Fun
After getting a babysitter, Greg, Kim, Jimmy and Christine go out to a bar, The Frolic Room, for some free time. Greg tries to get Kim to go out with them again, but Kim thinks the place is too dumpy for her tastes and doesn't want to go back. Until she gets ticked off after Greg tells her she's not fun like Christine, that is. So Kim goes to Jimmy and asks him how to be fun. Jimmy takes her back to the bar and helps her loosen up around other people -- particularly Greg.