Is there any way I can tell on these graphs the actual physical location of the routers on my hops? I'm not talking street addresses, just general cities. Thanks in advance for the help!

PingPlotter doesn't have any built-in facilities to help with this. There are a number of things you can do, though. An interesting guide on this can be seen here (I just used Google to find this - we have no affiliation with this site/page):

http://www.private.org.il/IP2geo.html

There are certainly tools available that have varying success at determining the location of a specific IP Address, some of them also doing traceroute. Google can certainly be your friend on finding some help for this.