Update question

Hi all - I wanted to ask about an update on my MBA. I asked around and it seems that other had serious problems after this - mac not working, booting, etc.
My updates are (other than the usual Safari, iTunes, etc):
- Security Update 2015-005 1.0
- MAC EFI Security Update 2015-005 1.0

Are those problem common ones, or a case by case basis? What do you think?

Another question - sometimes, immediately after when the Mac goes to sleep and I move on the trackpad to log in again - the screen appears black with only the cursor visible, then after few second the log-in screen will appear. Could this be caused by not sufficient disk space?

Thanks for the help

 

I'm not having problems per-se, besides the weird behaviour of my mac when the screen becomes black.
I wanted to know if there were recognized problems with the updates I mentioned, before updating and finding myself with a not-working Mac.