Fix to the crashing of client (windows)
The way that i stopped my computer from crashing after launching the client goes as follow:
Right click the LoL desktop icon. Go to >Properties>Compatiblity> And click the window in compaliblity mode and set it to windows 8. After that, launch the client as ADMINISTRATIOR and as you log in, spam click on the play button. It will or will not freeeze, if it does and you clicked the play button, wait 20-30 seconds and it should unfreeze. Hope this helped:)