How to mask everything except eyes?
Davinci Resolve lite is free, and it contains an excellent motion tracker.  By combining the motion tracker with a power window, and adding a color correction (to darken everything outside of the power window), you should be able to achieve the results you're after very quickly.  For tutorials on Davinci Resolve, search youtube for Alexis Van Hurkman.  He literally wrote the book on it (the instruction manual), and provides a generous amount of tutorials online for free.  Of course, he also has a complete course for sale through ripple training.  You can download Resolve lite here.