The simplest answer to the first question is to use the interpolation settings in the keygraph.   The 'anticipation' you're seeing is a natural result of spline interpolation. In some circumstances this long-lasting effect is what you want, but here it's not what you want!

So, use the mouse to pull a rectangle around James's Head, 
for the first 40 frames.  (This can be tricky; if you don't click just right,
you'll end up with only the first frame enclosed, or other strange things!)

Then click on Constant to more or less 'lock' the face for those frames.   
This will prevent the later change from affecting the earlier.

Or, pull a rectangle around ALL frames on the Head, and click on Linear.  
This will make any changes rather abrupt, but it will allow changes
on any frame and will eliminate the 'anticipation'.

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