Will a cohesive story make or break a game for you? If so, don't pick of Fable 2. Really, don't. It's a collection of some of the funniest, most enjoyable side quests and side characters you'll ever find, coupled with a slick combat engine and solid graphics, but all wrapped around one of the worst central plots and idiotic main characters I've seen in years.
You are a silent protagonist. For some, that will set off alarm bells immediately, because in a badly-told story, it means you'll feel like your character is only going along with the idiocy because they physically can't speak up and don't want to leave their companions to their dooms lest they (the PC) be held accountable for it. The villain establishes himself as the villain by shooting two children in their faces and only succeeding at killing one of them. Right off the bat, we're dealing with a two-dimensional cutout that made me long for someone as full of depth as Snidely Whiplash, and who is also a complete failure. You're the survivor of that pair, while the dead one is your sister. As the main quest gets into full swing, your asshole mentor (who routinely teleports to your objective after forcing you to slog through blood and steel to get there, then whisks the person/object you had to find away with zero effort) points to an ominous Spire in the distance, and tells you that's where the man who killed your sister is. Then she points you in every direction except that one
, and you're saddled with a cast of unlikable idiots (at best) and outright douchebags (at worst).
'Railroading' is a good term for this game. You're forced to go along with things no sane person would ever agree to, humiliate yourself for the amusement of other characters (re: the writers), and generally hit the constant crossroad of "Well, I could try doing the sensible thing...or I could do the horrible, stupid thing the game wants me to, because that's the only way to advance the plot."
Don't get me wrong: I loved so much of this game. But any time the writers had to plan something beyond a half-hour sidequest...I think that was beyond the scope of their ability. You'll meet lovable side characters, but also unlikable assholes the writers clearly thought were 'devil-may-care badasses' or something.
Play for the sidequests, forget the rest.