pdshext.dll - Explorer crashes when you right-click on a file.

Selecting a file and then clicking "File" (in upper left of screen) for list of optional actions also crashed Windows Explorer.
Only way to delete or rename a file was via PowerDesk, whose Context Menu and Drag-and-Drop Handler shell extensions turned out to be the cause of the problem.
Of course! Troubleshooting 101 Lesson 1 tells us to suspect the only thing that works as being the cause of everything else misfiring!
You must disable both extensions (in fact disabling or enabling either one of them produces the same action on the other).
I disabled the PowerDesk Drop Handler shell extension, too, as it, by itself, caused a right-click to "Hang" in limbo indefinitely.
I started with disabling all Context Menu extensions that were non-Microsoft Extensions. Bingo. Then I remembered Lesson 1 (above) and purposefully went right for the PowerDesk extensions.

The details of the shell extension that might cause the problem:

Shell Extension Name:	PowerDesk ZIP Extension
Filename:	pdshext.dll
Description:	PowerDesk Shell Extension
Company:	V Communications, Inc.
Product Name:	PowerDesk
File Version:	5.0.1.3
CLSID:	{26E7F081-EB97-11d3-9239-006008D2D00F}

If you think that you have similar problem in your system, you can try to fix the problem by disabling the specified shell extension. In order to do that, simply follow the instructions below:

1. Download and run the ShellExView utility from this Web page.
2. Find the right shell extension according the details specified above.
3. Select this shell extension and press F7 to disable this extension. After disabling the shell extension, check if the problem still occurs. If the problem still occurs, you should enable back the shell extension by pressing F8, and then try to search for another shell extension that might cause your problem.

This shell extension problem was reported by Curmudgeon1936