'scuse the necro, I never realised I got replies here...
So some updates... It's still happening and from what I can gather it's something to do with a hardware issue. I am running Windows 8.1, my friend offered to help with doing a system restore, though I don't think that'll help if it's down to hardware.
Apparently my video card drivers are up to date (I literally checked them a few minutes ago), I don't hear my fan anymore and I notice when my comp does do this (it'll randomly do it, for weeks it could be fine, other times it could do it three times in one day) that the vent at the side is super hot. Note the comp doesn't shut itself off, it's like the screen will freeze in place and the keyboard or mouse will not respond either.
I don't play games on the laptop, occasionally I'll place youtube in full-screen though I see nothing that links to why the comp does it... One time I switched it on and it simply froze before I could do anything with it, which makes me think overheating could be the issue, seeing as safe mode running four different anti-malware scans picked up nothing at all.
My HDD is 3/4 empty, I have very little saved on my laptop. I did a memory check, all was fine. I could also stand to run chkdsk again, just to make double sure. I also ran troubleshooters for everything I possibly could, all is working as it should.
I've put my laptop now onto a powersaving mode, hopefully that may or may not help. I'm also debating opening her up to see if I can find and get any dust and gubbins possibly clogging her up out, maybe find a loose connection that may need tightening.
Any help or suggesting something I might have missed would be great. My laptop after so many weeks of being fine has started doing this again and it's got be pretty down, so much that I dread switching the thing on sometimes.
Thanks for any extra help.