Compare between windows 7 and mountain leopard of Apples OSX

Hello

I would like my essay to be around 1000 words, and it should has a thesis statement.
The essay should have three main points
First point the history of the tow operating systems in general
Second point usability of both two systems
Third point ( you can choose whatever for the third point) as long as it talks about the two operating systems.
I have fe sources in PDF files you might need them.

I put 4 sources only, but you can use more if you like as long as you cite them
thank you