When I first got the 3DS I was playing almost exclusively in 3D. Now I usually leave it off. It's a cool effect in some games, and really impressive looking. But, I really prefer playing games the old-fashioned 2D way (same with watching movies). Plus, I find it can trigger a headache. Do you find you mostly play in 3D, 2D, or only one or the other?
I didn't find the right solution from the Internet.