MLK Won't start up! (Mac OSX Yosemite)

[Lolly]

Sooo, i've been having trouble lately with MLK, if you don't understand from the title, this might help you,
http://prntscr.com/6n2f5y
http://prntscr.com/6n2ffn

These pictures are from someone else's mac but the same thing is happening to me,
HELP!

:-\