I wonder if Bensheim's best bet is to max out his iMac with High Sierra and import his existing iPhoto library into Photos? (He probably doesn't need to go any further than Yosemite, but it may not be available to him.)
According to
OWC the highest an iMac 12.1 can go is High Sierra, and there are some limitations from Yosemite on (
ie. no handoff)
I agree that going all the way to High Sierra and Photos would be a the best long range plan, but given the recent upgrade to Mavericks, if we can get iPhoto working, I would encourage staying with Mavericks for at least a few weeks before jumping four upgrades to High Sierra. It is inevitable jumping that far will break at least some applications and involve a moderately significant learning/relearning curve. But that is just my opinion.
