Uninstalling VLC should remove all VLC context menus but might not fix the problem. If you want the VLC menu items don't uninstall.
It is true that correcting any value that may have been entered as a default action for the shell under the Directory key would fix the problem if that had been the cause of it. (Or adding back the needed value of "none".) If Windows finds an illegitimate value for default in the "Shell" key it will assign as default the first shell action on the list that it finds.
Thanks rogerdpack for pointing out the possibility of a problem with a default shell value. I have edited this post and uploaded a new version of the reg file with a new url to include your suggestion.
Here is a generic fix regfile to copy and paste into your text editor (Notepad or whatever plain text editor) and save as Folder-Open.reg with all files selected as the file type.
Windows Registry Editor Version 5.00
[HKEY_CLASSES_ROOT\Directory\shell]
@="none"
[HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Directory\shell]
@="none"
[HKEY_CLASSES_ROOT\Folder\shell]
@=""
[HKEY_CLASSES_ROOT\Folder\shell\open]
"MultiSelectModel"="Document"
"BrowserFlags"=dword:00000010
"ExplorerFlags"=dword:00000012
[HKEY_CLASSES_ROOT\Folder\shell\open\command]
@=hex(2):25,00,53,00,79,00,73,00,74,00,65,00,6d,00,52,00,6f,00,6f,00,74,00,25,\
00,5c,00,45,00,78,00,70,00,6c,00,6f,00,72,00,65,00,72,00,2e,00,65,00,78,00,\
65,00,20,00,2f,00,73,00,65,00,70,00,61,00,72,00,61,00,74,00,65,00,2c,00,2f,\
00,69,00,64,00,6c,00,69,00,73,00,74,00,2c,00,25,00,49,00,2c,00,25,00,4c,00,\
00,00
"DelegateExecute"="{11dbb47c-a525-400b-9e80-a54615a090c0}"
[HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Folder\shell]
@=""
[HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Folder\shell\open]
"MultiSelectModel"="Document"
"BrowserFlags"=dword:00000010
"ExplorerFlags"=dword:00000012
[HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Folder\shell\open\command]
@=hex(2):25,00,53,00,79,00,73,00,74,00,65,00,6d,00,52,00,6f,00,6f,00,74,00,25,\
00,5c,00,45,00,78,00,70,00,6c,00,6f,00,72,00,65,00,72,00,2e,00,65,00,78,00,\
65,00,20,00,2f,00,73,00,65,00,70,00,61,00,72,00,61,00,74,00,65,00,2c,00,2f,\
00,69,00,64,00,6c,00,69,00,73,00,74,00,2c,00,25,00,49,00,2c,00,25,00,4c,00,\
00,00
"DelegateExecute"="{11dbb47c-a525-400b-9e80-a54615a090c0}"
This will only affect the open action for folders. No other shell actions will be changed or lost. This key is from Vista Home Premium and should only be used for Windows Vista.
Instead of copying and making your own you can download this file:
Folder-Open.reg
http://www.fileshost.com/download.php?id=E0B51F081
It would be most wise to back up your Registry or do a System Restore point before using this file.
Unless one of the persons who actually has a problem replies to the thread, this is my best advice.