|Drugstore Cowboy (1989) [Nadine]: Dies (off-screen) of a drug overdose. Her body is shown afterwards when Matt Dillon and Kelly Lynch discover her in the bedroom; they then hide her body in the attic before Matt takes her out into the woods in a garment bag.
Fallen Angels: Tomorrow I Die (1995) [Carol Whalen]: Shot to death (off-screen) by Bill Pullman, along with everybody else in the cabin, when he eliminates all the witnesses. We only hear the shots from outside the cabin.
Terrified (Evil Never Sleeps; Tough Guy) (1995) [Olive]: Commits suicide. (Thanks to Gary)
Scream 2 (1997) [Casey Becker in 'Stab']: Stabbed repeatedly by the masked killer in a film-within-the-film sequence (re-enacting Drew Barrymore's death from Scream). The movie cuts back and forth between Heather being stabbed on screen and Jada Pinkett Smith being stabbed in the audience. (Thanks to Proinsias)
Lost in Space (1998) [Dr. Judy Robinson]: Killed in an explosion (along with Lacey Chabert, Jack Johnson, Matt LeBlanc, and Mimi Rogers) when a metero hits the ship as they try to leave the planet; their deaths are undone when William Hurt goes back in time and prevents the explosion. (Thanks to Mark, PortsGuy, and GLC)
Austin Powers: The Spy Who Shagged Me (1999) [Felicity Shagwell]: Poisoned after being trapped in a gas-chamber tube; Mike Myers then goes back in time and prevents her death.