it's a notebook so not a 65lb Mac Pro which are towers.
You do need the "101"
A Shift key to do Safe Boot
Command + r to get into the recovery partition and repair your drive and other things.
And always have some backups too.
Yes, install the updates.
Not sure what or why but generally a pre-existing directory issue, incompatible software or drivers. The usual stuff.
This also deals with unable to boot:
About Mac OS X Kernel Panics:These are two forums you want to use, read, and bookmart:
MacBook Series Forums
And of course the product support page and tech articles:
Your mac is so new it could have a newer build than what they tested the update for. Does happen.