well Vegetto, I think I figured out the problem. You see, I was playing CS 1.6 on Steam. Now, it WONT allow me to use OpenGL mode(which is what I do normally) so I put it on Direct3D. It seems that Direct3D gives people weird laggy mouses(it was happining to me in CS, but was constant). So make sure you're in OpenGL. I havent tried it out yet, but Im about to.
Edit: I had to reformat my harddrive, and anywards, it said my video card wouldnt accept OpenGL. I thought this odd, as it worked fine before. Turns out there was some update(had to root through system CDs that came with the comp). Once I updated the card, it works fine.