Hello Callump and welcome to Sevenforums.
BSOD ANALYSE Nvidia Drivers
It seems like you've updated your Nvidia-driver somewhere in June by looking at it's timestamp. Your dump, roughly, contains a causer on nvlddmkm.sys (Nvidia Graphic Driver). I will let you know a safe way to get rid of this current Graphic Driver, and have
no left-over files after your installation. Left-over files is in-length quite bad to have on the computer.
Driver Sweeper is a left-over cleaner.
A fresh driver
i) Make your way to
Nvidia Driver- page
ii) Uninstall the one you currently have and all its extensions
iii) Download
Driver Sweeper
iv) Get to safe mode (without network) and search for Driver Sweeper in your

v) Select all ATI components and analyse them
vi) Clean them, head into Windows
without internet and download the driver).
Here's the code for the interested ones.
Code Code:
BAD_POOL_HEADER (19)
The pool is already corrupt at the time of the current request.
This may or may not be due to the caller.
The internal pool links must be walked to figure out a possible cause of
the problem, and then special pool applied to the suspect tags or the driver
verifier to a suspect driver.
Arguments:
Arg1: 0000000000000020, a pool block header size is corrupt.
Arg2: fffffa8000149960, The pool entry we were looking for within the page.
Arg3: fffffa800014a260, The next pool entry.
Arg4: 00000000049004c0, (reserved)
LMVM Code:
6: kd> lmvm nvlddmkm
start end module name
fffff880`0f803000 fffff880`104e1000 nvlddmkm T (no symbols)
Loaded symbol image file: nvlddmkm.sys
Image path: \SystemRoot\system32\DRIVERS\nvlddmkm.sys
Image name: nvlddmkm.sys
Timestamp: Tue Jun 12 04:16:08 2012 (4FD6A668)
CheckSum: 00CBC27D
ImageSize: 00CDE000
Translations: 0000.04b0 0000.04e4 0409.04b0 0409.04e4 AVG
AVG is reporting problems. If it's the free version of AVG, consider making a chance to
MSSE. If you're having the paid version, consider contacting the costumer service, and make sure first of all, that you're having the anti-virus updated.
SFC /SCANNOW
End your actions by doing a
SFC-scan.
Best Regards,
Frederik.