I literally, just got home and plugged it in.. It currently has 10.8.2 on it, I'm wanting to erase all of the previous person's settings, data and such and don't know how! Will paying the $19.99 from the app store, re downloading the OS and re-installing allow me to do a clean wipe? I have a 27" i7, that is the previous version just before the new thin one... No restore discs came with.. Please advise my friends, Thanks!