I'm using my daughter's old mid-2010 iMac. I just want to see how much I would do on here versus my iPad so I can decide whether I'm gonna go back to an iMac. So I have it inside, and connected and I'm on it now. I'm wondering what the most recent software update is for the Mac, and if I should even attempt it on here (or if it would mess it up). It's running Yosemite right now, so I have no clue how far behind it is on updates. It's a 500 GB hard drive with about 78 gigs free. There are 178 gigs of photos stored on here. Ideally I'd like to, at a minimum, get all her photos backed up to a drive I could then use on a new (or 2017 refurb) iMac. What would be a good option for that? Thanks for the help!