One of my favorite movies of all time.
I watched this two nights ago at Tory's house, while installing Slackware on his new box. It was a VERY funny movie, staring the characters who played Jay and Silent Bob (actually, playing those parts) from the movie Jay and Silent Bob Strike Back.
Kevin Smith made this movie (as well as Clerks and Mallrats), with Jay and Silent Bob, before he made J&SB Strike Back.
Your plot analysis has a few holes:
There's two angels, Loki, the Angel of Death (who caused the plagues of Egypt described in the book of Exodus), and Bartleby, his sidekick (not really a sidekick, they both had pivital roles in events such as Sodom. I've forgotten his official title as angel, but it's not just 'his sidekick'.). After killing all the people the plagues were sent against, Loki felt guilty of all the killing (which is odd, because Bartleby later reveals that one of the two human weaknesses is a conscious, which implys that angels don't have one), and gives the sword back to God (symbolic of his resignation). God gets pissed, so.. send them to hell? Nah, worse, Wisconsin (we laughed SO hard at that). So, for a few thousand years these angels are walking around on Earth living a human's life (the other weakness of humans is their short lifespan, angels live forever (unless their wings are cut off, then killed)). Eventually, a Catholic church holds a "rededication cerimony" on it's centenial where anyone who walks through those doors will be sinless. That's where the fun starts. As Jesus said to Pope Peter, "whatever you hold true on earth, I'll hold true in heaven", the door's removal of sin became divine mandate, and if Loki and Bartleby walked in, God would be proven fallable and all existance would cease to be. Naturally, they have to be stopped, hence the movie.
In general, you kinda murdered the hilariousness of the first 30 minutes of the movie, but I'll forgive you. You should have just said that you watched it, and left it up to IMDb to explain.
One of my favorite parts of this movie is the Mooby scene, the entire thing with the board is well done and makes a point, but the ending of that scene is so great, even if you know it's coming.
Other than that, favorite quote:
Gun Salesman: We call this piece the Fecalator. One look at it and the target shits him or herself. Try it on.
Loki: Well, it's a lot more compact than the flaming sword, but it's not nearly as impressive. Just doesn't have that Wrath-of-the-Almighty edge to it. I mean, come on, how am I supposed to strike fear into the hearts of the wicked with this thing? Look at this...
Bartleby: Well, then, you know, don't use a gun. Just lay the place to waste, like.
Loki: Easy for you to say. You get off light in razing. You got to stand there and read at Sodom and Gomorrah, I had to do all the work.
Bartleby: What work did you do? You lit a few fires.
Loki: I rained down sulphur, man, there's a subtle difference.
Bartleby: Oh, yeah, I'm sure.
Loki: Hey, you know, fuck you, man. Any moron with a pack of matches can set a fire. Raining down sulphur is like an endurance trial man. Mass genocide is the most exhausting activity one can engage in, outside of soccer.