Except that I finally had the bright idea "hey, let me try plugging my cable modem directly into my computer!" and *boom* blazing fast connection instantly.
So yeah, apparently my router is dying/dead. Which is both "blah" because it means I need to replace it, and will not be doing the internet gaming (on console) thing until I do. But yay, at the same time, because I don't have to pinpoint the problem, or deal with the damn ISP in trying to do same.