[Framerate drops when changing weapons and zooming in and choppy mouse movement]

I'm having a problem where when I change weapons or zoom in with the sniper rifle the framerate will drop. I tried using this patch but it didn't work.

I also tried using dgvoodoo which helped a little but the framerate still drops. The other problem i'm having is choppy mouse movement even with the patch above. Any solution would be greatly appreciated.

[Mouse too sensitive even when changing settings, and look limited to left and right.]

Yes but it still moves too fast ingame. 

[Mouse too sensitive even when changing settings, and look limited to left and right.]

Hello, i'm having a problem where I'm unable to look anywhere other than down and when I use the mouse it just spins around really fast ingame. Here's what it looks like in action

https://www.youtube.com/watch?v=3EjVUnH2ItU&feature=youtu.be

Any solution would be greatly appreciated.