BSOD on notebook, Page fault on non paged area

Hello,
A week ago my laptop started randomly ( i think, cant find any similarities for the occurance of this)
popping the Blue screen of death. I runned a program and got some crash reports.
Please not that i havent updated anything of windows since 2011!!maybe that is relevant.
Info:
computer name: JIM-TOSH
windows version: Windows 7 , 6.1, build: 7600
windows dir: C:\Windows
Hardware: Satellite L655, TOSHIBA, Portable PC
CPU: GenuineIntel Intel(R) Core(TM) i5 CPU M 480 @ 2.67GHz Intel586, level: 6
4 logical processors, active mask: 15
RAM: 4151148544 total
VM: 2147352576, free: 1996627968

Errors:
On Fri 17/01/2014 08:47:03 GMT your computer crashed
crash dump file: C:\Windows\Minidump\011714-32183-01.dmp
This was probably caused by the following module: win32k.sys (0xFFFFF9600029F0DD)
Bugcheck code: 0x50 (0xFFFFF900C1FF5CF0, 0x0, 0xFFFFF9600029F0DD, 0x0)
Error: PAGE_FAULT_IN_NONPAGED_AREA
file path: C:\Windows\system32\win32k.sys

On Fri 17/01/2014 08:47:03 GMT your computer crashed
crash dump file: C:\Windows\memory.dmp
This was probably caused by the following module: win32k.sys (win32k!XLATEOBJ_cGetPalette+0x8AAB1)
Bugcheck code: 0x50 (0xFFFFF900C1FF5CF0, 0x0, 0xFFFFF9600029F0DD, 0x0)
Error: PAGE_FAULT_IN_NONPAGED_AREA
file path: C:\Windows\system32\win32k.sys

On Thu 16/01/2014 18:53:41 GMT your computer crashed
crash dump file: C:\Windows\Minidump\011614-41153-01.dmp
This was probably caused by the following module: win32k.sys (win32k+0xC46A7)
Bugcheck code: 0x3B (0xC0000005, 0xFFFFF960001946A7, 0xFFFFF88006DAF040, 0x0)
Error: SYSTEM_SERVICE_EXCEPTION
file path: C:\Windows\system32\win32k.sys

On Wed 15/01/2014 09:27:31 GMT your computer crashed
crash dump file: C:\Windows\Minidump\011514-27534-01.dmp
This was probably caused by the following module: win32k.sys (0xFFFFF9600027F0DD)
Bugcheck code: 0x50 (0xFFFFF900C1C26CF0, 0x0, 0xFFFFF9600027F0DD, 0x0)
Error: PAGE_FAULT_IN_NONPAGED_AREA
file path: C:\Windows\system32\win32k.sys

On Mon 13/01/2014 14:55:49 GMT your computer crashed
crash dump file: C:\Windows\Minidump\011314-33945-01.dmp
This was probably caused by the following module: ntoskrnl.exe (nt+0x70700)
Bugcheck code: 0x3B (0xC0000005, 0xFFFFF8000328F74E, 0xFFFFF880069AD010, 0x0)
Error: SYSTEM_SERVICE_EXCEPTION
file path: C:\Windows\system32\ntoskrnl.exe

On Sun 12/01/2014 21:54:56 GMT your computer crashed
crash dump file: C:\Windows\Minidump\011214-26535-01.dmp
This was probably caused by the following module: win32k.sys (win32k+0xC46A7)
Bugcheck code: 0x3B (0xC0000005, 0xFFFFF960000C46A7, 0xFFFFF88006EE9070, 0x0)
Error: SYSTEM_SERVICE_EXCEPTION
file path: C:\Windows\system32\win32k.sys

Thanks in advance, Dimitris