If you're interested in going the JAG route, do yourself a favor and read through this thread:
http://www.top-law-schools.com/forums/v ... 68&t=31543
It's the best source of JAG information I have found online. I did 6 years as an active duty JAG (National Guard now). My last couple of years, I did some recruiting for JAGs at law schools, and I always pointed students to the thread above for the best info online.
Which school you go to will not matter in nearly every instance. Most JAG Corps (and certainly the Air Force's, which I was a part of and did selection interviews for) hire from every law school - Cooley through Yale. We look for different things than other employers. If there is not something preventing your service (e.g., medical issue, cocaine problem, etc.), you can start increasing your chances of getting selected from day one in law school (and before, actually) and give yourself a very good chance of getting picked up.
For those who are interested in going this route, I would strongly suggest figuring out a backup plan in case something goes sideways. "Federal job" is an excellent alternative with a lot of carryover between the two.
For JAG selection, GW vs. Emory will not matter at all from a quality of school perspective. GW will get you a lot closer to internships and externships, which can have significant impact on getting selected. That would be GW's main advantage here.
Considering your goals, I'd recommend looking at scholarships at schools in the DC area. That will give you the most flexibility in case JAG doesn't work out. Also do as much research as you can on federal jobs that might be of interest and pathways to them (e.g., honors programs, PMF, etc.). If I had known what the non-GS pay scales were at certain agencies while I was in law school, I would have likely targeted those agencies, but such is life.
Each of the JAG Corps also use their JAGs differently, so it's worth learning the differences. For example, I think the Air Force does the best job at making sure all of its attorneys build the skills that would let them get federal civilian attorney jobs at nearly any agency.
One other consideration is that there is no better job for PSLF than the military, but that requires 10 years and trusting the program. Several JAG friends came in with $200k+ in debt knowing they were going to do 10 years. It's a roll of the dice though - that you'll get picked up and that the program will do what it says it will in 10 years.