Out of those I'd definitely go with #1. The second place would be great if it were cheaper, but as it is, I don't think it's worth it - gas is expensive, yes, but a 20 minute walk is still a significant distance from the office, and I think you might find yourself still driving more than you'd like. A 20 minute walk is forever when you're about to be late, or when you've just worked 10 hours and just want to go home. It might be a little more practical if you planned on biking, although that comes with its own problems. A 5 minute drive isn't that bad on gas either, which would be most of your savings.

I don't know how much you entertain, but it sounds like option 3 wouldn't be terribly conducive to it, and it sucks to have an apartment you can't bring friends back to later than 10 PM (at least not without feeling like an ass).