I have an iMac 2006 5,1 2.16GHz Core 2 Duo to which I have changed the RAM to 4gb. I want to upgrade the OS of 10.6.8 to a better OS, not sure which system. Ideally i would be able to watch films etc via Netflix or the like. Run AutoCAD design drafting software and sketch up. General admin/accounts for domestic use and simple Internet use. I have linux on my laptop so don't have issues but the iMac is storage of music and photos of my wifes and she is very pro apple. So best to keep it to apple OS. i managed to get thru to apple support who thought i had the best OS for that machine. But i am hopeful that i can get lion onto it.