Multiple BSOD occasions (possible driver issue)

So, hello guys! In advance, thanks for checking out my question, I really appreciate it!
Here's the story: I became a university-student in september in a foreign country, so I needed a laptop to study ... and spend countless hours playing video games. After a decent research, conducted from my father and I, we decided that the best laptop in our price range would be the ACER Aspire V3-772G:

CPU: i7-4702MQ 2.2GHz
GPU: GTX850M (aswell as an integrated Intel HD4600
RAM: 8GB DDR3L
HDD: WDC 1TB and the guys from my local tech-service also put an Intel SSD in (if that's relevant)
OS: Win7 Home Premium

So, what's my problem? While "studying" (that's code for gaming *wink wink*) I suffer from sudden lag spikes. I'm talking about dropping to 0fps (a still image) for a solid second or two. And this happens while I'm playing something at totally normal frame rates. I.e. - I'm playing WoW with 120 FPS, but when we engage a boss my computer just stopps for a split second and returns to a smooth framerate afterwards.

That wouldn't be a problem itself (atleast not a big one), but those freezes are sometimes BSODs and they happen without any context whatsoever. I recently noticed that they even happen while I'n NOT gaming and the PC is not being pushed at all. Aside from the BSODs there are some frustrating freezes of the whole OS (it seems), which last 10-15 seconds. The last straw was an hour ago when I had a ... grey screen of death - the whole screen was grey except for some white lines, which were flickering, and then the system rebooted. I've attached the debug.zip according to the instructions so I hope the answer lies within.

A possibility could be that I ****ed up something with my GPU drivers. You see, the guys at my computer shop had forgotten to install the drivers to the NVidia GPU, so my computer only ran with the internal Intel one until I found out. I installed the NVidia ones myself, so I could've screwed something up. Since the problems started I've already done some clean instalations of the newest GPU drivers, but that didn't seem to help.

Oh god ... that wall of text, I am terribly sorry! One last thing that I thought of - this could all be a RAM issue, but I don't have a clue what I should do if that's the case, or how I should identify it.
Alright, that's enough talking from me. I would really appreciate your help! If you need any more information, I will be willing to provide. Thanks in advance again!

I was actually exaggerating about the amounts of gaming I'm doing :) I am studying computer science, so I need my laptop a lot and I spend a lot of time infront of it.

On the other hand, I've set up the laptop to give me Kernel Files after the next error, but if I can provide anything useful in the meantime, I'll be glad to do it right away!