K so my band is pretty new and I have a question:

1) Our first show is in our school's auditorium, how should we set up? Basically where should we place everything so that every part can be heard by the audience.

-PA (160 W (Peak); 80W (Program))
-50 watt Vox
-50 watt Vox
-180 watt bass amp (thats what my bassist said but thats a lot of watts...)
-Drums set

Thats all we've got.
Honestly, your wattage doesn't mean much, since I doubt that you'll be running anything at full volume. And yes, your bassist is right; a solid state bass amp will have a very high rating. Have your PA pointing inward, so that the sound would meet where most people will be. Don't point them straight out. Same for guitar amps, a slight inward angle will be fine. The bass amp is going to disperse like crazy so I wouldn't worry too much about positioning on that on. I'm assuming that the amps you are using are combos, in which case I would try to borrow a couple of cabs; they help increase your amps dispersion.
Your drum kit will be overpowering the sound of every instrument, or at least it should be that you can all hear it. Set it up at the back with the bass amp nearest to the drummer so that your drummer can still hear the bass while he's playing. Then set up all the PA and guitar equipment a good deal in front of that, where you guys are going to stand. The drummer should be able to hear the bass, but you guys only need to hear the drums to know where you're going.
The way I set up on stage is thus (from left to right):

Rhythm Guitar - PA Cab - Drums - Bass - PA Cab - Lead Guitar

In terms of depth, I put the guitar amps out in front, with the bass amp slightly behind, angled in toward the drums; the PA cabs are on either side of the drummer, positioned and angled so that he can hear vocal cues. The bass amp is on the side of the drums with the high-hat, so that the bassist can follow the basic count of the song and hopefully keep everyone tied together.

Rear: PA Cab - Drums - PA Cab
Middle: Bass Amp
Front: Guitar Amps

Keep in mind that I'm not referring to the very front of the stage - just a few feet forward from the PA cabinets.

That's just the way I do it. Your mileage may vary.