I must confess I am not good at debugging XP BSODs, but I'll try.
I would start by removing Avast, as you seem to be getting some sort of network error.
Use this tool: http://files.avast.com/files/eng/aswclear5.exe
MSE is the recommended replacement: http://www.microsoft.com/security_essentials
Also, remove CCleaner for the time being, as I suspect it may be deleting your minidumps.
It may also pay to do some hardware tests.
For RAM: http://www.sevenforums.com/tutorials/105647-ram-test-memtest86.html
For hard drive: http://support.wdc.com/product/download.asp?groupid=613&sid=3&lang=en
If you get more BSODs, manually upload them.
Summary of the dumps
Code:
Built by: 2600.xpsp_sp3_gdr.100427-1636
Debug session time: Thu Nov 4 11:43:04.562 2010 (UTC - 4:00)
System Uptime: 0 days 1:41:52.294
Probably caused by : fltmgr.sys ( fltmgr!FltpFastIoQueryStandardInfo+28 )
DEFAULT_BUCKET_ID: INTEL_CPU_MICROCODE_ZERO
BUGCHECK_STR: 0x8E
FAILURE_BUCKET_ID: 0x8E_fltmgr!FltpFastIoQueryStandardInfo+28
¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨``