This is why I stopped modding systems.
I say start at the games which interest you most. I also have a lot of games to catch up on, but I prioritize. I beat XenoBlade and am nearly done The Last Story, and then I plan to move to Mass Effect 3 next. I've been in a RPG craze, so I'll likely pick up FallOut: New Vegas and beat that too, then play finish Tales of Vesperia and Fire Emblem (Wii). After that I dunno, If Halo 4, Metal Gear Rising, or Resident Evil 6 go on sale, then maybe I'll pick up a copy, otherwise I'll work on whatever games I have left for my systems and work my way down from the best games I have yet to beat. Zelda: Skyward Sword, Star Ocean: The Last Hope, and Infinite Undiscovry will by 2012 projects, and after that I might start.....anyway, enough ranting.
If you have trouble sticking to a single game, play something short. Go beat Metroid: Other M, or something, just so you can have a finished game under your belt, then tackle something longer, and more interesting to you. Maybe have a game like Halo or Bayonetta on the side, something you can pick up anytime and enjoy, so you have something to play when you're not in the mood to sit down for hours at a time.