For SSN, the lower last 4 the better. Mine is 07xx. I was #4 of 28; #1 and 2 were previous UAL employees so they went to the front of the line.
First, I HIGHLY recommend that you live in domicile. In your case, driving distance of DIA. You don't want to commute; it'll take years off of your life. It's doable, but decreases QOL bigtime.
Let me give you junior man in seat from Jan's SSC report:
737:
Den: 8085
ORD: 8071
DCA: 8044
Fifi:
DEN: 8083
ORD: 8079
DCA: 8034
LAX: 8074
SFO: 8021
Those numbers are seniority numbers; the higher, the more junior.
There are more airbus bids, so I'd recommend bidding fifi. And I'd do it in the following order (based on personal experiences for commutability): DEN, LAX, SFO/ORD, DCA. SFO and ORD are a tossup; I'd go for SFO ahead of ORD because there are a ton of commuters to ORD, not as much to SFO.
Chances are, there will only be a couple of guppies in your class and I'd expect it to go reasonably high (but I find it odd that junior man in system is 737 DEN). If your only choices remaining are the guppy, I'd rank order: DEN, ORD, DCA.
If you don't get DEN right away, you should be able to get it fairly soon after training. Unless vacancy bids stop, you'll get it within 6 months. Good luck to ya.
Edit: full reverse has some great advice. I guess that'd move ORD up the list for bidding for ya; just make sure before bidding that those guys haven't traded yet. And ask anyone ahead of you in class if they intend to trade with one of the guys looking for a trade.
There shouldn't be any reason for the more senior guys to screw over the junior ones. In my class, I made it very clear that I'd be taking a panel to ORD, as did the guy senior to me. Those lower in the class were able to do the mental gymnastics. Also, I wouldn't hesitate to ask anyone in front of you with ORD fifi bids if they planned on trading them for DEN just prior to bidding.