Hi guys, This may be a really obvious question to some of you (and I hope it it) but i'm not the greatest at keeping my machine running as well as I know it can. I bought the 27" i7 iMac when it first arrived (oct 2009) and since then I have simply been using it and have neglected keeping it running as well as it can (besides software updates). I use it primarily for graphic design just so you know. I ultimately want to upgrade to Lion as I'm currently running Snow Leopard 10.6.8 but want to know if there's any basic stuff I can do re Disk Permissions etc before I get my machine ready for an upgrade. I have been told about resetting your machine/clean installing your machine once a year to keep it at its optimum performance. So i'm a tad confused now. Does anybody have any pointers on how to go about getting my machine ready for Lion or will a install of Lion overtop of SL be fine? Thanks in advance!