I guess the issue I'd see with this (with experience DMing for 3.0/3.5 since they were first released, so a decade or so) is that I'd have to rule that a character with a 2 intelligence can't even take any feats that would require anything beyond animal instinct to use. Endurance, Weapon Finesse, etc would all be ok, but feats like Weapon Focus, Combat Expertise, or most others would be incomprehensible to you. Not to mention... with a 2 INT, your character has the brains of a wolf or smart moose. I have yet to see one capable of using a weapon it doesn't grow itself, meaning that if I were your DM, your hopelessly brainless barbarian wouldn't have the mental capacity to use a sword, axe, or spear. You would be spending your game time punching things, kicking things, and trying to bite them, all of which have very little effect either due to their design (the human jaw and included teeth are not good weapons) or because of a lack of training.
Good luck with it, though I can't imagine enjoying a character that can't even understand words beyond 'sit', 'stay', or 'down'. It'd just get boring taking orders (dog commands?) from the other players all the time.