There are a few different issues you mention in your post:
1) Securing port forwarding
Port forwarding is a direct result of using network address translation. Port forwarding provides no security, but enables routing of packets from a port exposed on your external network, to an address on...
I recommend the Y series from Lenovo... http://shop.lenovo.com/us/en/laptops/lenovo/y-series/ There may be a student discount available somewhere....
Those games you play are pretty lightweight, so a cheap Dell laptop may work just fine as well.
"what happens when you phone is off and you get a call? It says the phone is off.. so..im guessing they can "ping" your phone.. Yes? because you get back a message the subscriber can not be reached. "
As Akizu mentioned your phone will broadcast a power-down message.. Even if that message isnt...
If you value build quality, portability and battery life over raw performance, then I would go for the mac book pro.
Right now there is a known bug in the keyboard in the 13" mbp retina, so I'd wait for them to resolve that before buying.