Hi, I'm having the exact same issue you're having. It's completely random! Sometimes it's when I try to uninstall an application or game, other times it will be when I right click on a folder to delete or rename it. I most recently had it happen when I clicked on a shortcut on my desktop to try and delete it.
I had this issue with Vista; but only recently. It must be something to do with a recent update.
I found a "fix" for this issue; however, it's on a fix if you have the registry key listed that they want you to disable; I didn't.
This is one of the fixes. How to fix “Windows Explorer has stopped working” in Windows 7 | Web Talk