I thought of that, but it intentionally traps us in a position where we're bound to be surrounded and unable to escape, in an air-tight confined space full of noxious smelling meat, potatoes and dairy products (provided it hasn't been hauled off -- still, suffocation hazard). Industrial freezers open outward too, so there's no way we could secure the door.

Okay, diagramming floor three has clarified things.

Room 31 is in the corner of the building, where alley 1 and the other exterior wall meet. Fifteen feet before room 31 is a short hallway going to an elevator. Elevators are almost always near the front of a building. Therefore, the building faces an unknown street as originally thought. Going away from Main Street means less time spent in the alleyway.

I thought of an alternative regarding the nature of the infection. It amounts to roughly the same thing as the red-blue hypothesis, but the mechanics are somewhat different.

The Zerg Hypothesis
Everything is infected with the same strain of pathogen/parasite, just as the Zerg are all the same. However, different creatures are under the control of different remote "cerebrates" -- Benny, Noface, Nicole, The Red (Noface and/or Benny), or The Blue (probably Nicole). This control is not fixed; it may vary with distance from the different cerebrates, personal decisions of the infected creature, or some other factor. We were originally blue, but have been becoming progressively more red over time.

This would explain why we've been going particularly apeshit since being separated from Nicole. It also provides an explanation for Jesse's lack of red awareness -- she's currently blue, so she isn't privy to the "team chat".

Naughty Nancy is a midget sex slave. For the love of god don't open that door.
http://www.youtube.com/watch?v=lPpI2ev7AeU

So left has the highest probability of going outside.

But mysterious hallway.

This is the first time that the writing has been blue -- it's always been red up to this point, and seems more helpful than taunting this time ("How's your mother?").

The pressing question is how in the hell are we going to get out of here. They are a hivemind, and know we're here. The fact that we came in through a side door suggests the front door is going to be left or right, and since we ran down the alley a distance, should let out on a street parallel to Main. However, we don't know whether we went left or right to go into the door.

Investigate the spooky hallway it is.

As an experienced "drainer", I can testify that the sewers are a really bad idea. One, manhole covers are very heavy and require the proper tools to open. Two, as has been said, sanitary sewers are usually too small to move around in. Storm sewers are usually fairly large, but they're more common to areas with heavy rainfall and access to a local body of water (river or ocean). Three, while it is possible to feel your way through a drain, a light source is almost required, more so when there's headcrabs running around inside. Even when there's not, they tend to contain debris, hanging sheets of rusty sheetmetal, and other stuff you don't want to crawl around in the dark. Four, sanitary sewers can contain gasses which can literally paralyze and kill humans with a single breath, particularly when they've been sitting stagnant (as these likely are).

I don't know about the other choices. Pawn shops tend to be heavily fortified -- it's questionable whether we'd be able to break in.

Some of you seem to have forgotten the details about the rifle. It shoots tranq darts, which Jesse said doesn't affect the critters.

Edit: oh lawl, the voting closed yesterday. Disregard this.