Thank you bobw.
You DID miss something! I ASKED if the version was 10.3.2
And I DID mention the installer disk!
Funny, yesterday night the same happened to me again (slowing down etcetera)
I did a hard restart and my computer stopped rebooting and the disk stopped spinning minutes after at...
Your version is 10.2.3?
Careful, I am no nerd. I react because it took me several days to solve and no Apple dealer knew an answer apart from reinstalling a new system.
Similar things started to happen to me after upgrading to version 10.2.3 and that on several computers.
Repairing disk...