Simple and easy module. You can choose which categories you want to see on the main page of your site.
Just unpack the files from the upload folder to the root folder of your site. Go to the administrative section of your site. Go to the Extensions->Modules. Find “Categories on main” module and click “install”.
Go to the administrative section of your site. On the modules page select “Categories on main” and click “edit”. Select the category you require: