You had the same problem before you installed Diablo II or before you fresh installed Windows?
If the problem persisted despite a fresh install, most likely it's a hardware issue (although drivers can cause this also)
I'd suggest trying the built in Vista memory diagnostic because this is an error that occurred in memory. Here's instructions on how to run it: http://www.bleepingcomputer.com/tutorials/using-vista-windows-memory-diagnostics-tool/
Because of the consistent difference between parameter's 3 and 4 of the error messages I'd really suspect a driver over a physical memory problem. So, to troubleshoot the driver problem we'll have to run another tool.
Before running the tool backup all your data, find your system restore/installation disks, and have access to another system that can connect to the internet. This is because the next test that we run has the ability to prevent you from getting into Windows - if the error occurs within a driver that loads before the Windows logon becomes available.
Once that's done, go to Start and type in "verifier" (without the quotes) and press Enter
In the window that opens, click on "Next" to create the standard settings
Then, click on "Next" to automatically select unsigned drivers
Then click on "Finish" to verify the list of selected drivers.
The point of this is to generate a memory dump - so expect the system to crash on you. If it doesn't crash immediately, keep using Windows until it does. Once you capture the memory dump analysis post it here for us to have a look at.
Once you've crashed, go back in and turn off the verifier (until you do this the system will continue to crash because of the verifier).
To do this go to Start and type in "verifier" (without the quotes) and press Enter
Then select the "Delete existing settings" option.
Then click on "Finish" to close the dialog and remove the settings.
If you're unable to do this in normal mode, try going into Safe Mode.
If you can't get into Safe Mode, then you'll have to access the Recovery Environment in order to manually remove the settings (and that's not fun!).