Lag/stuttering while mouse looking has gotten unbearable

[LiQuid]

Ok, I'm realizing now this is something really wrong with my PC as I've starting playing Destiny and the mouse is acting spazzy as HELL in that game too... I took some quick sample vids of my going back and forth from gamepad to mouse control in that game:

https://www.youtube.com/watch?v=Fsmm1Nx86zA

and an even quicker one showing what happens to my mouse when I'm rolling it around over Chrome/Windows vs. over gameplay.

https://www.youtube.com/watch?v=fVO_Sz5j1Xo

I'm hesitant to say it's a hardware issue (a friend suggested I was maxing out my CPU, which is admittedly bad) because it happens in EQ which doesn't even TOUCH my CPU.

I know this probably puts my issue outside the scope of p99 tech support, but I'm at a loss for what could be causing this. Googling as hard as I can and I'm being told to get a new mouse pad, like wtf....