The only effects you can disable are the Visors (by using EFB to Texture), else you'd have to go about making/finding AR codes.
How demanding AA is depends on your GPU and your other graphical settings. I dunno about the GT 740M, but at 2x MSAA at 2x IR, it's probably not bottlenecking you or slowing you down. To be sure, disable the Framelimit, then compare your max speed (in the same spot, use save states) with no AA and 2x AA. If you notice a difference, your GPU is slowing you down when you enable AA, if not, feel free to leave it on, although 2x MSAA isn't that much quality-wise.
How demanding AA is depends on your GPU and your other graphical settings. I dunno about the GT 740M, but at 2x MSAA at 2x IR, it's probably not bottlenecking you or slowing you down. To be sure, disable the Framelimit, then compare your max speed (in the same spot, use save states) with no AA and 2x AA. If you notice a difference, your GPU is slowing you down when you enable AA, if not, feel free to leave it on, although 2x MSAA isn't that much quality-wise.