Sheshadri,
System Views are shared across the Organisation. What you could do is set up Personal views and then share them only to the appropriate Teams that make up your Business Units (Dynamics CRM creates a Team for each Business Unit).
If you are using Role-Based Forms, the configuration of which views to use in SubGrids and Lookups can be set in each Form variant.
Whatever defaults you try and force upon the Users, each User can set their own Default View for each entity (see blog.xrm.com/.../set-default-views-microsoft-dynamics-crm-2011), so maybe you could roll that into your training?
Best Regards
Chris