Multi Player Arenas
This section will have pictures of all of the arenas in Perfect Dark, as well as description.  So you can check here to see if you haven't unlocked a certain arena yet.
The Skedar arens is a simple level to memorize, because it doesn't have a lot of twisting hallways.  It has a few big main rooms, and a few straight halls.  A great level for beginners.
The Sewer level is all narrow hallways.  I don't really like this level, because if you are fighting more advande dplayers and simulants, they will tear you apart in these halls.  There is a small part where you can go underwater, which is pretty neat.
The Grid has a great blend of narrow halls, and large open areas.  It is still a smaller level, too, which means there will be a lot of action.  There is a glss floor in one of the rooms, wich you can shoot through, sending shards of glas everywhere.  There is also an elevator, which can be used to set traps.
The Ravine is a large level.  It is mostly open areas, with a few tighter hallways.  This level is great for explosive weapons, because you have a chance of getting out of the way here.  It can be a little difficult with automatic weapons, because there is no where to hide if you get caught unarmed.
The Base isn't a very good level.  It has a very basic layout, wich isn't bad, except that the level is mostly small corridors.  There are only a couple big rooms, and even those aren't that big.  There is a glass walkway, which is pretty cool, but that's about it for this level.
Area 52
Area 53 is a fun level.  There are towers that campers can hide out in, and annoy everyone by getting lots of kills, and there are lots of small buildings throught the level which makes it great for capture the flag and other team games.
Car Park
The car park is as basic as a level can get.  It is a few levels, which are all the same, connected by 4 different staircases.  Planting gun turrets and dropping grenades down the stairs is fun, but the most fnu is on the rooftop of the building.  This is a very large level, so make sure you have a lot of simulants.
The Fortress is another very basic, yet fun level.  It's main floor is 4 narrow walkways, which it is easy to shoot people off of.  There are lieele spots that can be used to moniter these walkways, and you can hide out in them and knock everyone off them.  Very fun.  This level is great for team games.
G5 Building
The G5 Building has some narrow catwalks also.  What is fun about these, though, is that if you run fast enough, you can jump from one to the other!  There are mostly narrow halls and corridors in this level though.
The Pipes level is named after the floor of pipes that it has, even thought that is only a small part of the level.  There are lots of very narrow catwalks in this level, that are easy to get shot off of, or even to just fall off of if you aren't careful.  This is a fun level for a lot of people at once.
The Villa is made after the solo mission, Carrington Villa.  Much of the level is big and open, and it is a pretty simple level to rmember.  The neatst part is a high walkway, that you can jump off of onto a small platform.  Very fun.
The Warehouse  is a very large and open level.  It has one room which is a series of stacks of crates, and yuo can jump from stack to stack.  You can also get shot off of them, which isn't as fun.  The main room has a very high stack of crates, which you can jump off of onto some walkways that go around the side of the room.  This is a great level.
The Temple is a large level, but is also very easy to memorize.  This Goldeneye level has an extremely simple floor plan.  It also has a bunch of very large rooms, which are fun for using explosives.  It has great lighting efects as well.
The Complex is also a level from Goldeneye 007, and it is a classic.  Many narrow halls and rooms that look similar, this is one of the most difficult levels to memorize.  But if you are able to memorize the whole thing, you will be able to easily defeat anyone else in this level.
The last Goldeneye level, the Facility, is one of the most fun.  It is a medium sized level.  It consists mostly of wide hallways, but it has a few large rooms, and a few small spots.  Overall, many people prefer this level to any other.