Magento has a huge number of features and there are probably few businesses that will need to use all of them. If you want to disable some features completely for your site (such as the newsletter, or the tag cloud), you can do this easily through the administration options.
System > Configuration > Advanced > Disable module output
Find the module that you want to disable and select ‘Disable’ from the drop-down box. For example, if you want to disable the newsletter feature the config will look as follows.
Save the settings, clear your cache, and the feature should be disabled.
It is still possible that some parts of your site refer to the disabled feature. For example, if after disabling the Mage_Newsletter module you still see HTML that is related to the newsletter, it means that that HTML bit was not generated through the Mage_Newsletter module and so you will have to remove it manually from the template.
Disabling modules only in one store
This applies to multi-store setups. As with any other configuration option, you can use the configuration scope box at the top left of the System > Configure page to define whether you want to make your changes for all stores or only for one store.
Select an option from the drop-down box before you save the settings that disable the module. The ‘Default Config’ option applies the changes to all stores that do not override the setting explicitly. To disable the module only for one store select that store from the drop-down box.
How do I find out the name of the module I want to disable?
In the case of the newsletter feature the name of the module to disable is clear (Mage_Newsletter), but here’s what you can do if you can’t figure out the module name that easily. If the module outputs html for the template, you can look at the block name of the html output. The first part of this name should be the same as the module name (this has been true for all the modules I’ve checked so far) . For example, the block Mage_Tag_Block_Popular is output by the module Mage_Tag. The rest of this post explains how to display block names in the template.
Here’s how you get Magento to display the names of the html blocks. In your development environment, select one of your stores in the Current Configuration Scope box (see above). Then go to:
System > Configuration > Developer > Debug
Enable the Template Path Hints and Add block names to hints.
Now access a page that contains the module you want to disable. You should see the block names written in blue around the html elements that belong to that block. For example, the sidebar of my product listing page contains the newsletter sign-up elements and the tag cloud. The block names for these elements are Mage_Tag_Block_Popular and Mage_Newsletter_Block_Subscribe. The first part of these two names ‘Mage_Tag’ and ‘Mage_Newsletter’ correspond to the module name that output these blocks. If the blue names do not appear over the red box, move your mouse over the box and you should see the blue name appear.
Note: Disabling a module will not only remove the HTML output of the module, but also all functionality associated with it. So, for example if you disable the Mage_Newsletter module and you have customers who are already signed up for the newsletter, you will be unable to send them emails. If you just want to remove HTML elements you should modify the template, instead of disabling modules.