What does Google really track?

I'm using a VPN to log in internationally to view search results in certain countries.

1) What is the most optimal way to ensure that I'm not being tracked - set up virtual server and create my own VPN? (I imagine my MAC address is still being tracked despite using a VPN?).

2) Using a more popular VPN (which most good VPNs probably are), does Google "discount" Page Rank or disregard traffic from VPNs?

Thanks very much in advance!

well they peep on you through webcam in your lap thats for sure