I came across this page on accident. It might finally solve my quest for a movie that has been on my mind for roughly 10 years I would guess.
I was extremely young when I watched this, so bear in mind details are patchy.
It was around Christmas time, maybe New Year's, and I had the night perfectly planned; first I would watch the Buzz Lightyear movie, and I had timed it perfectly so after it finished Star Wars: The Phantom Menace would turn on, then a movie that, when I read about it in the TV Guide (I'm from Australia by the way), sounded amazing and I was hooked before I had even seen it.
From memory this is what I know:
A group of people, male and female enter a building.
A nerd, I think, in the group said it was like a video game he played.
Inside the building they start dying, one by one. The nerd, from what I remember, dies because he thinks he can "cheat" by going towards what I think was an elevator and there was possibly an orb he put his head into. Either the doors or the orb cut his head off.
In the end, if I am not mistaken, a male and female adult exit the building from a pipe with a little girl or boy into a "new day." At the end of the pipe or tunnel is an extremely bright light.