So I just bought a MacBook from a friend. An early 2011 MacBook Pro 13'' with an i7 processor. Lately it has been running really, really slow. I have nothing on it besides a few pictures, Skype, League of Legends, and Sophos Anti-Virus. I uninstalled both League and Sophos (although I'm not sure I uninstalled correctly.) Safari is slow to load, it has about a 3-5 second delay just to open a new tab, and about 5-8 seconds to open a page. Theres delay to view pictures on my desktop. What can I do to make it faster? Or at least, not as slow. Also, would i be able to completely reboot my MacBook? I don't have the installer disc thing, but i hear its not necessary. Please help, thanks in advance.