Windows Registry for New Menu with Batch Files

How can I add an item to the 'new' context menu?

This shows how to add items to the "New" dropdown menu. How about taking them away?

Also, I want to make a batch file that automates this. Like this:

@echo off
echo Enter you file extension
set /p ext=
copy con ext.reg
echo Windows Registry Editor Version 5.00 >> ext.reg
echo. >> ext.reg
echo [HKEY_CLASSES_ROOT\.%ext%\ShellNew] >> ext.reg
echo "NullFile"="" >> ext.reg
start /wait ext.reg
del ext.reg
echo Complete
exit

1. Anything wrong with this, in general?


2. Can you write to other types of non-text files like registry files with batch files?


3. Please tell me the registry code for removing an item, so that I can add that.


4. Most importantly, can a registry file interact with the user, like take in input and make a variable so I don't need a batch file at all?