My Laptop crashes sometimes while playing games or watching videos what may be wrong?

[Herakuresu]

I have encountered blue screen, as well as my laptop to freeze while playing a game(L.o.L.) or while watching a video on VLC.It's 5 years old already and i did a clean up + a format on it.Even though now it doesn't suffer from over heat problems,the freeze up problems seem to pop up more and more often and I thought I should get some help from you guys,to bring some light into my problem .When i say "freeze" i mean the operations of the laptop,the screen normally shows corrupted colors mixed up and the sounds going "electric" (while watching a video)
The model of the Laptop is :Sony Vaio Notebook VPCEC2M1E ,with Windows 7 Premium x64 operating system, 2,27 gigahertz Intel Core i3 M 350, 500 Gigabytes Usable Hard Drive Capacity, AMD Mobility Radeon HD 5000 Series , 4GB RAM.
I believe that this laptop had unique features and totally worth every penny I spent on it.I would be glad to hear your thoughts and suggestions.Thank you all for your time !

 

[Delfinos]

Might run a memory test.

memtest86 is a free tester that works really well, just burn their iso and boot on it letting it run until it shows failure.
If no errors overnight its not the memory. But if its the memory its an easy fix ^^

Just if you open it up be gentle with them cables...
Vaios printed cables break from a loud sneeze and you might not be able to see it

 

[D_Know_WD]

Hi there Herakuresu,

I guess you should start ruling things out as a possible cause for the issue. You can start with testing the RAM as Delfinos already suggested. After that, it may be a good idea to test the HDD with a brand specific testing tool. The results will show you the overall health status of the drive.
You can update your GPU drivers as well.

Cheers,
D_Know_WD

 

[Herakuresu]

I downloaded the memtest86, i couldn't run it 'cause i am a newbie but why can't i delete it completely?Any leads towards this?
Also I will take my laptop from check up once more 'cause I am not qualified in knowing what problems i can fix and if i can really fix them on my own.
Thanks both of you!By the way,I had run a program to stress my graphics and i didn't see any problem, I don't know what's going on on my laptop and right now I am trying to delete any malware that my laptop may have with various programs like AdwCleaner,Malware Anti-Malware,JRT and HitmanPro as suggested by one fellow while replying to one's problem with an .exe .Problems,problems everywhere!

 

[Herakuresu]

I think i found a lead to my problem,I did a little research and i found in Event Viewer the main problem is this : RegSetValueExW etc any leads with this?