How to disable and enable magento's default block

Generrally in magento store some of the default functionality and modules are there which comes by default in some location.Some people needs these default blocks and some don't.That means they need to disable those undesire modules or blocks.In this article I am going to show you how to disable some of default modules and blocks of content, like the callout banners in the right and left columns, or the poll, or newsletter signup.Also here you will be getting two different ways for disabling default modules and block content like:

Get list of categories ,subcategories and sub-subcategories in custom script

This tutorial is going to show you one of the ways to list all sub-categories and sub sub categories through custom script for your Magento store.In This script I have shown all subcategories on the basis of main category means Root Catalog's Id.
If you change the $id = 1 then it will display suabcategory upto the first level that looks like below.

Magento: How To Subscribe Customer Email Id To Newsletter Subscription List Automatically

Sometimes we need to auto subscribe the customer email address without knowing to customer if he visit to our site or click on any events in the site .So in magento that functionality is also available but that generally goes through customer permission .but here you can set by below code to newsletter subscription list .

Magento: Using Or And And Query Condition To Collection

Please check the below details how we can use AND and OR query condition in magento collection.
Product collection :

Magento: How To Get List Of All Modules Programmatically?

One of the most great advantages of magento is it supports various of modules to install for a different type of work.Also it has default modules,So for knowing how many modules installed in magento and to check whether that is active or not please follow below details: