Assuming you have 7.1 SP2 (the latest) you should set up a Managed Software Delivery Policy. You can apply that to a Target built up of machines with iTunes and machines you want to remove iTunes from and it will then run whenever the PCs pick up the policy.
First off you need to look in Manage > Software > Newly discovered software and find out how many different versions of iTunes you have. You then need to work out how to silently uninstall each version, this SQL will help:
SELECT Distinct DisplayName, DisplayVersion, UninstallPath
FROM dbo.Inv_AddRemoveProgram
WHERE (DisplayName LIKE '%itunes%')
What you do next depends on how the silent uninstall works. Broadly speaking you create a Software Release with a command line to uninstall and a detection rule. Then you can right click the Sofware Release > Actions > Managed Software Delivery to create a Software Delivery Policy.
You also need to think about uninstalling the other allied software you may or may not want, Apple Quicktime and Apple Application Support.
Application Denial to stop people running iTunes is another option.