You type yast<enter>
Not sure about the case, been a while since I used SuSE.
You could try YaST, or other combos, maybe start typing
Y and press tab twice to look for valid completions, do
the same for a lowercase y ...
As for the safe: that'll depend on your hardware, I don't
think there's a globally safe setting (unless maybe plain
old VGA (640x480x16) does it).