In our CRM site we are not using some entities like lead and contracts. We want to hide these entities wherever these entities are displayed. I want to hide these from file - new - lead from all the forms and sub forms availble in crm 3.0
Simply remove all the rights of those entities from the user's roles. If you remove the read and other rights of Lead from a role then user who have only those role will not see Lead entity in MS CRM.