Guitar
My advice as a guitarist myself: Stay away from the video games. Focus on the guitar itself and whatever lessons you can find (I know several great online lesson systems for lead, never poked around for bass.).
Play. Play, play play. Play often. Try to set aside at least an hour a day to practice. Noodle around on it throughout the day. Never put that thing in its case, keep it on a stand near you. Put guitar magazines and lesson books near wherever you relax (The john is an excellent choice here! lol). Always have something that reminds you of your guitar around.
You will prob feel at some point your fingers are too big or clumsy and you just cant fret it clean or fast enough but you will. Just keep doing it.
I hate to sound like one of those cheesy motivational speakers, but it really is all about the motivation.