Imac Photos Crashing

[Fiddlegal]

Trying to read many posts regarding this issue. In the last week, Photos is locking up my iMac. I have to power it down. Force quit does not do it. When editing, the photos start pixelating for the lack of a better word, then the iMac locks. I am currently running OS10X El Capitan. My iMac is late 2009 model . iPhotos show pictures from 2006, but they are blanked out from the transition from iPhotos to Photos. Suggestions?

Thank you!

 

[cynics]

Try repairing the library. I had a problem the app wouldn't close properly and required me force quitting the app every single time.

CMD + Option + left click photo app.

Select the "repair" option. After I did that the app started functioning perfectly again.