Do you want to remove some items from the new context menu that you don't use (at all)? Then continue reading.
I only use new folder, new text document and rarly create a new shortcut, but I think that create a new shortcut can be useful so I didn't deleted it.
Anyway, open a registry (Start key + R and type regedit). Expand HKEY_CLASSES_ROOT.
After you've done that, be sure what extension type you want to remove. If you are not sure, click on new context menu and create a new file e. g. new text document.
New icon is created. Notice the file extension* (in our example it will be New Text Document.txt) and inside HKEY_CLASSES_ROOT, find the key with that extension (.txt) and inside that key, you will have ShellNew key which you should delete.
Remember to make a backup of that ShellNew key if you decide that you want those items back.
Some extensions have ShellNew key one level deeper, e. g., .doc file type will have ShellNew in HKEY_CLASSES_ROOT\.doc\word.document.8\ShellNew and some file types will have ShellNew in root of the extension key, like so HKEY_CLASSES_ROOT\.psd\ShellNew.
When you are faced with a new extension, do the same as above to find it, and once you find the extension and ShellNew key, delete it.
For a Briefcase is a bit different. Briefcase doesn't have any extension, so instead, you need to find a Briefcase key in the HKEY_CLASSES_ROOT and inside that Briefcase key, find a ShellNew and delete it.
On this picture, ShellNew is already removed.
Restart in not required.
Some programs tend to create a ShellNew key once they are run if ShellNew key doesn't exist.
But you can create a .reg file to automatically delete.
Create a new text document, rename it to some-file.reg and inside that file enter like:
Windows Registry Editor Version 5.00
And repeat that with every extension you want to remove.
* If you don't see the extension, you need to go to Control panel » Folder options » View tab and uncheck Hide extensions for known file types