Windows Explorer stuck in a crash loop with Windows completely unusable (even in Safe Mode)

Oh, you ruled out the hardware, I typed this answer before I saw that.
Then the only possible thing is that files are corrupted and you will need to reinstall,
or you need to do remote debugging with WinDBG and a USB Debug or a Firewire cable.

If you have changed the frequency, the problem is unlikely to be Windows 7.

As stated it does not seem like you can get in the BIOS to reset it, thus try it like this:

• Shut down the computer, pull the power plug and disconnect any other cables.
• Open the computer and take the BIOS battery out for some time.
• Place it back and close your computer.
• Connect your cables, power and start the computer.
• Go to the BIOS and check the settings, you might want to reset another time to be sure.
• If this doesn't work to solve the problem please comment on my answer.

The BIOS battery looks like this:

I had a similar issue. It seems that what caused it for me was trying to customize explorer using command line. I ended up with the copy/move crash, and open-in-new-window issue.

This is the command that broke things for me:

%SystemRoot%\explorer.exe /e,/root,::{450d8fba-ad25-11d0-98a8-0800361b1103}

I chanced upon this case, and it seems that resetting folder options in the registry might keep you from having to do a system restore, or recreating the user. Here's the related KB.

I ended up only having to delete and recreate BagMRU, and Bags (I compared my registry before and after corruption for differences, I also compared to the MS case).

[HKEY_CURRENT_USER\SOFTWARE\Classes\Local Settings\Software\Microsoft\Windows\Shell\BagMRU]

[HKEY_CURRENT_USER\SOFTWARE\Classes\Local Settings\Software\Microsoft\Windows\Shell\Bags]

There were more differences, but this was the first I tried and it solved at least the open-in-new-window issue. I wasn't experiencing the crashing anymore because I had done a system restore.