Fable is tamed and very fun for younger gamers IMO. Halo 2 is more for the grownups (not meaning age of course), more intense yet teenagers of all ages play it too. Yes there is co-op in H2 in the campaign mode. You can do split screen. I think you and your sister will have a blast with either except that you can only play one person in Fable. Fable is cheaper of the two games if you buy used. If both of you like FPS and Star Wars, may I also recommend Star Wars Battlefront. Very fun and has good replay value.
__________________
Namaste
|