I have an Croe 2 Duo iMac from 2009. It's fairly slow. First of all, I wonder if I should upgrade to Mountain Lion. It's not a huge deal for the new features, but if it improves performance, I would like to do it. Does it have any possible slowing down of the machine? Secondly, and less important, what are some easy ways to speed it up? I'm thinking about adding RAM, but until then is there anything I can do? My hard drive has tons of space. Thanks for any help!