The game may run perfectly for you in general, but lags you once you start trying to aim.

This isn’t entirely a mouse acceleration / input problem, but rather a Call of Duty Black Ops 2 lag issue from the game itself.

To help improve or fix your aiming situation, you’ll want to do the following steps below.

Do note that future game patches will also help this issue and provide greater compatibility with people’s mouse and keyboard situations, as well as hardware specs.

— Turn off Shadows
— Turn off Ambient Occlusion
— Set Texture to AUTOMATIC instead of having it set as extra
— Turn off Sync Every Frame (like VSYNC)
— Lower your resolution
— Upgrade to latest NVIDIA / ATI / Intel drivers (they have released updated drivers for improved support for this game and it solves bugs, glitches, and lag issues)

It may not fix the problem entirely for you, but it WILL improve it.

This has been tested on Windows XP, Windows Vista, Windows 7, and also Windows 8 — with noticeable improvements on each.