Repeated Blue Screens, how can I stop them?

Okay, firstly I couldn't find where to post this, as my laptop is running Vista Service Pack 2, so I posted here instead (sorry if it's an inconvenience). Anyway, my laptop keeps having the blue screen error, and when I turn it off and on again it generally restarts fine. But generally, within 4-6hours, it does it again. It's becoming very irritating.

When I log back on, it says "Windows has recovered from an unexpected shutdown" and this is the box it gives:

Problem signature:
Problem Event Name: BlueScreen
OS Version: 6.0.6002.2.2.0.768.3
Locale ID: 2057

Additional information about the problem:
BCCode: 1a
BCP1: 00005003
BCP2: C0802000
BCP3: 000092D9
BCP4: 629FF601
OS Version: 6_0_6002
Service Pack: 2_0
Product: 768_1

Files that help describe the problem:
C:\Windows\Minidump\Mini031811-01.dmp
C:\Users\Owner\AppData\Local\Temp\WER-57969-0.sysdata.xml
C:\Users\Owner\AppData\Local\Temp\WER3F02.tmp.version.txt

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Can anyone help with what to do?