If I want to animate my char would it be better to just keep the detail level for the render/animation up or would it be better to just copy the Armor/etc.remove the multires-mod till it has its basic shape and then baking the details as a normal ?
Both options are valid. It depends on high "authentic" you want to be honestly. Baking the details as a normal map is optimized and better for render-times since there's significantly less geometry to calculate. However normal maps are by nature a visual trick and not "authentic" so-to-speak. Whereas if you leave the multires intact and turn it on when rendering (after rigging and animation) all of the detail is authentic and geometry based. So in a way it's the highest quality render possible. Though it will take longer to render.
Does that help?