WordPress 4.5 – upgraded and now plugins (all of them) are not working

I’ve upgraded and first got a 500 error after updating some plugins (something like “this website cannot handle this request…) I was able to open my cpanel and rename the plugin directory, that worked, then I narrowed the issue down to 4 plugins (the ones I had tried to update) –
Ditty News Ticker, Embedly, Popup Builder and YoastSEO — I really only need the Yoast SEO at this point but when I try to delete these plugins (after renaming the directory back to “plugins”)- It says it was unable to delete the old version of the plugin …

Now, in my dashboard, it says that I have 48 active and 48 inactive plugins (all the same ones), but on my website none of the plugins are actually “active” or working.

Any ideas on how to fix this?

Lisa