I'd like to see the driver listed for the 7/12 error - can you post that entire dump from the blue screen text please?
Meanwhile, from your first post it appears you've been getting these errors for quite a while, though not every day. So let me suggest the following:
1) Please look in device manager - any yellow or red symbols? If so, please tell us with which devices they are associated
2) Please run checkdisk as follows: right-click on a command prompt icon and open as administrator. In the command prompt window type: chkdsk /r
(then press ENTER). You'll be told the disk is in use and asked if you want to run checkdisk on the next boot. Say yes, exit the command prompt window, and reboot.
3) Is Vista Service Pack 2 installed? If not, please install it: http://www.microsoft.com/download/en/details.aspx?id=16468
4) Please check Ram: To check the ram, download memtest (http://memtest.org/
). Burn it to a cd using a dedicated .iso burning utility (http://www.petri.co.il/how_to_write_iso_files_to_cd.htm
), make sure the cd drive is at the top of the boot order in bios, then boot to the newly created cd and run the utility.
5) Please run full scans with BOTH AVG and MalwareBytes -- what is the exact message you get about a broken digital signature from AVG?
That should keep you busy for a while