Hell, if both is an option then definitely both. I love both for different reasons. I'm an apocalyptic addict and love that realm a lot more than the somewhat cliche, mostly 'normal' fantasy that Skyrim has; but the actual world, interaction and all around MASSIVE exploration of Skyrim is leads, bounds, and lightyears ahead of Fallout 3. So on that note, I'd say get Fallout 3 first since it'll take FAR less of your time and you'll finish it first if it's one or the other for now. I actually love Skyrim and it's world, it's gorgeous, but in terms of what I prefer, I'm much more apocalyptic prone, hence my immense excitement for F4. It'll have the exploration of Skyrim plus the upgraded graphics, sound, everything! That's another thing, you're going to have the option (if you have the means to play it, dunno if you're playing on PC or not and if it's got the power if so) to play what is hopefully going to be F3 on steroids and just all around better, so Skyrim might be a better option for now. But we'll see if F4 lives up to expectations. I can't imagine it not.