I'd say after updating, you should take a breathier. As for getting better less lag in game, sorry to hear you have that problem man.
A member in my gaming group has use fixed with Optifine and Fastcraft and many other boosting mods for less lag and better FPS, so I know a bit about
changing settings from him lol
I'll talk to him when he gets on and see if there is any other mods or settings you could use to get better performance.